Here are some things i've noticed or think need to be tweaked about the new planet colonization system.

I think the new planet colonization techs are too easy to get too. As it is now, it just extends the colony race, you just have to run straight to those techs. And you can get them one after another, and colonize any planet you want. Or like in the game's i've played, trade techs for them after only a few turns. Maybe they should be spaced out? or integrated into the tech tree, some further down the line?

Also, on the GUI side, the terrain maps on the new planet types, they're very bright and primary, and kind of hard to focus on, at least for me. On the green one, i can barely see what tiles are outlined in green. What about making some "oceans" on the special worlds? Like methene oceans that could be greenish, or putrid toxic orange oceans, just to vary the terrain a little bit more?