To wage war is not a challenge to taken lightly.
Ignoring your opponents alliances, or the killing off of trade routes, or the war tax, where is the impact on your nation. It’s all a bit too easy.
It seems wrong that 2 ships can defeat a planet. Or one if undefended.
How can you transport 1 billion soldiers, tanks, ordinance onto a ship instantaneously, yes you built your ship, hit launch, by a miracle they are just there ready to fly.
Lets face it each man would need 4 cubic meters at least in order to sleep, store weapons, personal items (cos it seems they are going there for the rest of their lives, well maybe not). Therefore 1 billion troops takes up 4 billion cubic meters, or 1 cubic mile, pretty big
(try not to laugh too loud) Now if your flying for 10 weeks you’ll need to phone home every so often, take a shower, eat, keep fit, etc so in reality you are looking at 10 times that.
Put them in cryo-stasis I hear you say, sounds good, but research it, put it on a tech tree somewhere probably towards the end of the tree. But its still 1 mile cubed.
Tanks/planes/missiles/transports probably big beasts so were back to 10 times bigger. So we either have a huge spaceport or space shipyards (or even multiple space shipyards), lets face it even the "death star II" in star wars was only 100miles in diameter, no 10 mile wide/long launch bay there.
I propose new starbase type of "shipyard", for building large/huge/"hugecargo" ships, huge cargo being a new transport type. Although in starwars – attack of the clones at the end you see the clone battleships taking off from the surface I would suggest that is not really feasible for a 300 meter multibillion ton ship to take off, such thing as escape velocity to overcome. Tiny/small/medium ships I can come to terms with, bigger than that needs a space based shipyard… Oh yes!!!
In war the enemy will target your ability to wage war and that is likely to be manufacturing facilities/shipyards first, but since you have to conquer a planet to take out the manufacturing plants having the possibility of taking an expensive shipyard out might add to the game play in a war.
If a nation on earth was to build a nuclear silo out of the blue 1000 miles from your capital city, with a nation you know one day you’ll come to blows with. Would you sit back and say, it’s ok, I don’t think he’ll us it. Would you
a) Build a strike team and take it out?

Build one yourself.
c) Demand they take it apart and submit to inspections, or it’s war soon
d) Bribe them to take it apart and submit to inspections.
Hmm If you can build one yourself then cool, if you can’t then lock and load cos options c and d is not possible, If you already have one then build another or yep you guessed it lock and load.
What do you think will happen when that country is Iran… kind of true to life really.
North Korea might have been bribed to take theirs apart.
Ok, take a break, and continue in 5 mins LOL
One other thing about troops, a population generally consists of a certain composition, the uk for instance http://en.wikipedia.org/wiki/Demographics_of_the_United_Kingdom#Age_structure
Has 66% of population between 15 and 64, its fair to say a man can fight on the battle field to say 45, after that it’s probably a command role of some kind. And lets say 17 is the youngest. Were left with 70% of those and most women will be running the planet, I know I’ve seen starship troopers but at most 10% of women will go to war. So maybe were looking at 25% of the whole population will be eligible to be troops.for a 16 billion planet that’s 4 billion troops, but by the same token it’s also 4 billion troops to defend. I can see the devs will have a nightmare integrating that little gem into the gameplay. So I would suggest that for a 16 billion planet only population over the 8 billion mark are allowed to be soldiers for offensive. (yes 50% but makes the maths easier) and over 6 billion can be defensive troops (66%) – (greater than offensive due to knowledge of land and troops dug in etc)
Seriously if you leave 1 man on a planet should that planet be able to pump out 100 research 50 mp and 100 credits?... answer is obviously no, but it can happen in this game (well ok 10 million might be the lowest in this game)
Also can we not commit genocide too often without being expelled from the UN and massive sanctions imposed? Occupy planets, (those manufacturing plants have ceilings 1 foot too low for your super large race…LOL..how can you use those?) and soldiers add to population, of course people won’t be happy but that also allow the planet to revolt should nearby influence be too low. Maybe declare independence.
Binding treaties
Treaties that can’t be broken,
e.g. we’ll stop the war if you give us 100 credits per week for the next year. if the credit cannot be taken/given then the treaty is cancelled.
Or we’ll give you planets x,y,z and 30 per week if you do not enter our current territory for 60 weeks. The territory is taken from the moment it’s signed, any additional territory gained after that is ignored and can be entered.
Some changes are in order.
1. No more than 10 million troops per ship, or maybe 2 million per module
2. Research levels of cryo storage (5 levels big units to tiny units)
3. New starbase type of shipyard, with all new fancy components to aid in the building of large ships
4. Only troops over 50% population capacity mark can load onto transports.
5. Binding treaties
Advanced changes
1. Option to commit genocide, immediatly expelled from UN with trade cancelled and not possible with all UN nations, unless compensation paid (lot of money)
All of the above might be planned for GC3 if they are tell us so we can start dreaming.