Some random thoughts :
- Invasion Defenses seem underrated compared to the rest. I rarely (if never) built them on my planets in GC 1, and considering room limitation in GC2, the defenders should get an interesting bonus. A fully upgraded Invasion Defense should nearly compensate air superioriy but it should be very expensive to maintain (top anti-air defense, guerrilla training for the population, etc.).
- What does the bonus for neutral races stand for ? It is an interesting concept though.
- I am still a strong advocate of planetary invasions lasting more than one turn. I have no idea how you can invade a planet with billions of people in 7 days, except if you use extremely radical invasion methods... An initial attack could have 3 outcomes : invasion successful, invasion repulsed and invasion turns to guerilla war (the latter case being more likely when the defending planet is highly populated). This would give an opportunity to the defender to break the blocus and bring some reinforcements. Furthermore, slowing down the attck could be one side effect of Invasion Defense buildings.

We generally want to favor the guy doing the invading. They're the one who had to load up troops from across the galaxy and send them over. 

Even as-is, you could end up with a race who focuses largely on technology ending up with a scenario such as:

Attacker: 5

Defender: 1+1+1+1+1+1 = 6

That would get incredibly difficult to overcome.  We plan to have a galactic achievement that adds an additional +1 to all your planets. 

And on top of that, imagine someone who focuses on techs that improve the quality of their soldiers, you could have someone whose planets are VERY tough to conquer without doing massive orbital bombardment.

I perfectly understand that the attacking civilization hould get a huge advantage, especially if the whole population counts as soldiers on the defending planet. A civilization unable to prevent invasion ships from reaching its planets should be in big trouble. I even think that every invasion (failed or successful) should hurt the defending planet, causing huge infrastructure damage if destructive invasion tactics were used, provided that the attacking player committed enough troops to invade the planet.

I believe (maybe I am wrong) that Invasion Defenses (if not providing a huge bonus ti the defender) will seldom be a wise choice. Planetary room is a very scarce ressource in GC II and maybe the most precious (like high quality planets were in GC I). Except if Soldiering technology is extremely expensive, I'd rather research 2 technologies to get a +1 Land bonus (valid for every fight, atacking or defending) instead of building Invasion Defenses (valid only when defending and on certain planets) on every planet, to avoid wasting maintenance costs, planetary room, and useful time. Technology itself should moderately improve your fighting ability, but the most benefits should come from its practical implementation.

I disagree about room. If I have a class 15 planet then those 15 tiles coudl be used:

1 for advanced farming: +15 food
1 for virtual reality: +40% morale
3 Mega factories
3 Mega research centers
1 Planetary Achievement reserved
1 Stock exchange
1 Orbital control thingy
1 Super project reserved
1 Planetary Defense
1 Invasion Defense
1 for whatever

Only early on do you really need 5 factories to be getting much out of the planet.

What about being good makes you a better defender(your ppl luv you and will do their upmost too defend ye) and, being evil makes you a better attacker?(IE:your insanity scares everyone and will do whatever they can to avoid death...). hmm what about employing commanding officers of planetary invansion? the better ones may cost more but have better tatics...random events and moral standpoint give you a selection and,if you select one their is a risk that the commander you picked may die in the line of duty... and have planets resent your rule for a while (like civ4 sigh...and, many others.). also a more devloped "nation" can defend itself Not by being more technologized, but by having to pay more maitance...also maybe you can bulid Mil.Bases on planets that allow you to construct transport mods and, allowing you to appoint one of the generals to defend your planet? hope some ppl understand what im saying.... anyways i got civ4 a while ago but lost my comp (im get real angry so i smashed it it sux anyways). so im hoping to be able to play later...

I am still a strong advocate of planetary invasions lasting more than one turn. I have no idea how you can invade a planet with billions of people in 7 days, except if you use extremely radical invasion methods... An initial attack could have 3 outcomes : invasion successful, invasion repulsed and invasion turns to guerilla war (the latter case being more likely when the defending planet is highly populated). This would give an opportunity to the defender to break the blocus and bring some reinforcements. Furthermore, slowing down the attck could be one side effect of Invasion Defense buildings.

I agree. Love the officers/commanders idea aswell.

Planetary Invasion more than one turn ?

Why can not an invasion happen in one turn ?

A turn equals one month.

If Aliens do exist "and No I do not want to get in that debate" could not a Alien fleet conquer Earth in one month ?

I seriously doubt it. Especially if we were at the same technology level as they were.

And a turn is one week, not one month.

I am pretty sur an alien fleet could invade Earth (a relatively small planet in the universe, with only 6 billions inhabitants) in one week. Of course, it would require using extremely destructive invasion tactics or a much superior technology. Using conventional warfare against a more populated planet having a similar technogy would take much more time on the other hand, even if the invader has complete air superiority.

i think we should be able to decide where to land on the planent or what order u wanna try and take over the planet end. u could set up ur base in an open space or take over a farming district. naturally that'd be easier to take over and it would take more troops to take over the intial colony. u could decide just to nuke one whole sector like a market or something. and the embassy being one building would be a highly fortified area thats just easier to arieal bombard. i also liked t he commanding officers lets go with that.

"What about being good makes you a better defender(your ppl luv you and will do their upmost too defend ye) and, being evil makes you a better attacker?"
-Lowa

I like! I mean, consider - would you rather be attacked by Orcs or Amish? Er, bad example, but maybe Orcs versus Knights of the Round Table. The Knights would be falling over themselves trying to entertain their prisoners and offer them tea, while the Orcs... well, let's just say you wouldn't need to dress formally for the invasion to impress the officers.

On the other hand... when the going gets rough for defenders, I would NOT want to be stuck with a pack of hungry Orcs. Or especially lead them, considering that officers get first dibs on rations and assassination is the surest way to promotion in armies of evil. And that's aside from the fact that your typical Orc is cannibalistic. Knights, on the other hand... just sing a jolly song about valor in the face of certain death, and watch the suckers sally forth!

Yes, this does indeed sound like a good call.

I even think that every invasion (failed or successful) should hurt the defending planet, causing huge infrastructure damage if destructive invasion tactics were used, provided that the attacking player committed enough troops to invade the planet.

Bad answer. That was the case at some point in GC1, and it lead to the tactic of invading a planet not to take the planet, but take much of the infrastructure/PQ with you. Do that a few times on the enemies major worlds, and he would have had 80B population on an uninhabitable world. It was hard to mount an invasion against that many people, so you'd just throw one transport at the planet, use a dirty invasion method, and wait for the people to start dying.

I disagree on making planetary invasions more complex. This isn't a combat simulator, I don't want to get bogged down in details that don't directly pertain to the running of my empire.

popup target has a point... but i dont want my fate to be decided on a click of the space bar and how decked out my ships is alone. it is a strategy game. lets throw in some strategy

It's been brought up before that you're not the general/admiral of whatever forces are in combat. You might get to decide what resources those in battle get, but you didn't draw up the battle plan, and you might not even get the chance to approve of the plan if it isn't very important or very high level.

I've never seen a 4x space game that had tactical combat where you weren't forced to fight the combat yourself if you wanted to even come close to the full potential of your ships. I've had times I'd auto-fight a fleet battle, loose most of my ships, reload and manage the battle, and not loose a single ship. The problem with that is, if that's what it takes to play effectively, then I'll do it for every battle, and then I'm spending more time managing combat than I am running the empire. If I want to play a fleet battle simulator, I'll find a game that does that well.

This is a prime example of the difference between strategy (overall, I want to conquer them, decision making) and tactics (nitty grity, you go there, decision making). Of course you have to have some tactics in a game like this, as even directing individual ships (or groups of them) would be a job for the Admiral and not the "President" when it comes to attacking places. But you would never have the President (Overlord of multiple worlds) on the battlefield, directing battlefield tactics. The only series I've played that combine strategy and tactics in a way that makes sense is the Total War series and that's because they're set in a time when kings and princes did command their armies on the battlefield and so would need to "be there" and good tactics could win the war.

As to the question of "failed" invasions hurting the infrastructure of a planet, I would say "Yes", but only if that infrastructure somehow includes the population. This would mean, for example, that a planetary bombardment of a planet with population 6 Bil would leave only 3 Bil (or so) even if the invasion failed. Which might lead to a tactic of sending in a first wave invasion to soften up the enemy, followed by a traditional invasion.

p.s I think all the stuff on Good/Evil/commanders giving defending/attacking bonuses should come down to a single Morale bonus, which could be something like; Good or planet having an ~80%+ population happiness would mean a +1 defending Morale bonus, Evil or planet invasion force came from having a ~70%+ pop happiness would mean a +1 attacking bonus...