You've managed to recreate, in a modern take, the cool feeling of the beginnings of Spore. I see you've built from elements you've already mastered, that's good! Experience and memory can inspire new solutions :)
The skill-tree is a pleasant surprise (we all love evolution), I would put a visual icon or something in every box to make them pop out when looking at the entire tree.
Sorry for your loss. At least you got few decades of knowing him!