Tone down your earthquakes. Only once in a long while should you risk an earthquake that can bring your CC down.
Also, while it's nice to have a chance for the blight to enter the game, try to make it so it is controlled by the player. That means no massive earthquake that destroys the A Lab prematurely, thus ending your game :/
The AI base still has one very narrow free entrance, even after the lava is settled.
Try to use just one eruption per volcano, or a max of two. And try to not erupt just all volcanoes. Some of them just erupt after they're already surrounded by lava, thus not making much sense.
Do give the player 2 residences to start with on Hard. It's not exactly hard to keep the colony alive, but it takes way too long to start growing your colony in size. Maybe remove a little more pop.
Disasters are too frequent. It becomes annoying hearing all those alerts and you can hardly keep track of them, looking out for that one disaster that may actually affect you.
EDIT: Did I mention Day/Night? If not, please give us day/night
Scrap the AI's microwave turrets, they're worthless. Also, if the AI gets 5 MHDs to start with, what's the use of giving it Tokamaks?
Oh, and you might have some infinite loops lingering. I know I somehow got into one.