How about a way to increase the amount of tiles on a planet.
Ie: An advanced terraforming tech.
Just being able to upgarde the yellow and green unusable tiles isnt enough really.
Take mars for instance, making it have more than 4 tiles at some point would be very handy.
As it is its just barely habitable. I usually leave it alone and just nick it back with a transport ship after another civilization has colonized it as it isnt worth the trouble.
