since the game is out, I take the liberty of coming up with a feature idea. basically, what I have in mind is an alternative to planet bombing, a ship that is stuffed with invasion troops and if victorious, can take a planet with all upgrades and most of the population.

I plan to base the combat progress on infrastructure points that are already in, so they serve as a defense against both bombing and invasion. one big question is of course how to stop a player from bombing for a while and then finish the rest with invasion troops and get a mixture of fast (and cheap since it requires fewer invasion ships, see below) and good (since you take over the planet development). what I thought of is that if planet hp goes below certain thresholds there is an increasing chance of development upgrades destroyed. say, below 2.000 there is a 50% chance to lose a pop 2 upgrade, below 1.500 the odds increase to 90 and if already destroyed there is a 20% chance of losing some other upgrade.

play around with the numbers to make it balanced, the point is, bombing is quicker, but it also negates the very benefit you wish to obtain. I dont know if it can be coded, but it seems a reasonable approach.

now, to the ships themselves. what I imagine is basically something along the lines of a siege frig, but maybe at a different level. most importantly though I would like to make them one-time use only. so its an investment, you need to guard it and since you will need a few of them to get the job done, you will have to balance the benefits you obtain (no res. and time to develop the planet) vs the cost (the res. sunk into building the ships are effectively lost). I would like to see a small drop in planet pop when you build them, just to depict the training of a big troop contingent, i.e. the conversion of civilians into military forces. I would see them work as each causing a set number of dmg over some time, like a single frig doing something along the lines of 400 - 600 planet hp damage (depends of course and needs balance). so you land them and watch your own and the enemy planets hp go down. if it reaches 0 with pop still intact the planet is yours. I do need to sort out how the system should distinguish invasion and bombing damage, but something could be found I guess.

the nice thing about it is, it involves trade-offs, decisions. its not a no-brainer, it has its own risks and is not approporiate for any planet, only for the developped ones. plus, it opens up research options, like more damage for invasion troops, better defense against invaders, higher resistance of developement upgrades and so on.