Planet must lose some population on invasion

[afwbkbc]

It's both realistic and will improve early game balance by preventing rapid doubling and tripling of population by capturing natives when lucky. If planet's population will be reduced by 40-70% - that would smooth this curve, because some time will be needed for it to grow.
This will also smooth ridiculously fast increase in power when you can walk over some weak AI and take everything, your industry/research graph simply skyrockets in these cases.
Additionally, I'd add "rebel resistance" or "oppression" bonus to conquered planet that will reduce industry and research production by 50% and keep happyness below 5. This will go away in 20 turns but a building can be added that mitigates it.

[Vezzra]

You're right, that's a problem, actually conquering is far too easy in general. We plan to change this and make military acquisition harder, and having certain serious long term consequences. It definitely should become much more difficult to integrate new species that way into your empire. Also, an alternative, peaceful/diplomatic method of integrating new species/natives into your empire is planned. It will work slower and require different resources (influence), but the advantge is that integrating new species this way will have far less negative long term consequences.

Which makes sense - someone who you try to force to cooperate at gun point is much more inclined to cause you trouble than someone you've been able to befriend and convince to join your cause.

I'd add "rebel resistance" or "oppression" bonus to conquered planet that will reduce industry and research production by 50% and keep happyness below 5. This will go away in 20 turns but a building can be added that mitigates it.

Probably not exactly that, but something along these lines. "Rebel troops" are actually already in the backend code, just not useable yet.

[MatGB]

Probably not exactly that, but something along these lines. "Rebel troops" are actually already in the backend code, just not useable yet.

Yup, I found and used the icon for the Advanced Ground Troop Pod when that was introduced as placeholder art with a different colour is better than the same colour for both pods.

It would definitely make sense for population to be lost on invasion: it would also make sense for it to be lost during a sustained blockade, it's one of the reasons I keep toying with the idea of having some of the growth techs keyed to Infrastructure instead of planet size, if your city is repeatedly bombed it's likely to lose population, etc.

But that's one of those longer term ideas.

Another thing I dislike currently is the troop numbers on a planet immediately after invasion: they appear to have a fairly random value and then grow really quickly, with the limits on troop pods being built keyed to troop value on site they need some consistency, and I'd like to have trooop growth immediately post invasion be restricted in some way.

[afwbkbc]

It makes sense if troops count after invasion = offensive troops count - defensive troops count and wouldn't grow while 'oppression' bonus remains. There also should be mechanism to bring additional troops on planet. I.e. troop ships could have "Add troops" button on owned planets.
Also it would be realistic and balanced to reduce number of troops on planet that built troopship. Also add "Mobilization" focus which increases troops quickly at expense of population (planet will ignore troops cap in this case). So built troopships won't just get infinite number of free troops out of nowhere, but take them from actual planet.
So planet must either increase troops natural way or via mobilization before mass-producing troopships.

This will really prevent snowballing conquest - you won't be able to make 200 troops from 10 troops anymore. Conquering will become more smooth and require some difficult decisions (i.e. sacrifice population on some planets).

[Vezzra]

There also should be mechanism to bring additional troops on planet. I.e. troop ships could have "Add troops" button on owned planets.

Yes and no. Yes, we need to provide some means by which you can "transfer" troops to planets where you need more of them, but not via troop ships, that would quickly become a micromanagement nightmare.

We've already discussed some ideas along that line, and I'm quite confident that something like this is going to be added at some point.

Also it would be realistic and balanced to reduce number of troops on planet that built troopship.

Actually, that feature is already there, but IIRC correctly has been temporarily disabled because the AI can't handle it. But Geoff already implemented the required mechanics, both for troops and for colony ships btw., IIRC.

Also add "Mobilization" focus which increases troops quickly at expense of population (planet will ignore troops cap in this case).

Hm, I have to admit, like this idea. I wouldn't remove the cap completely, but at least raise it significantly (that is, several times of what the normal cap would be).