This is super cool. As someone who uses shader graph and other tools with node editors pretty frequently, it's awesome to see that style of scripting built into a game. The performance of the node editor was great for me.
I agree with others, that the game would benefit from simple scenarios at first before ramping up to a planet-scale (or moon-scale) simulation with an entire fleet of terraformers. I had fun playing around with it, but the learning curve towards making a graph like the one in your screenshot was a little too steep!
I really hope you stick with the node graph concept as a way of programming AI. I love AI-programming games but most of them lack the depth you can achieve with a system like the one you have here.