Oh right, so hello there!
I'm a new redshirt guy, so today was my first contact with the game. After playing it for three hours, let me throw some thoughts around:
1) In the advanced start menu, there is an option "% Land". It confused me a bit at the beggining - there is no tooltip explaining what this is about. I figured it's probably land/water ratio of the generated world (right?). But since, you know, I've not seen the game before, I did not even know there is water involved. So that was just a bit confusing.
2) After the game started I obviously had no idea what's going on and what to do. After two hours I still don't know what "Landing Site's" difficulty is (it will probably have meaning in later acts, right?). As you said earlier, there's tooltips missing to a lot of stuff, so for example after two hours I still did not figure out what do natural wonders do and how to use them. I assume you'll add explanations and tutorials to all that stuff, so I'm not gonna rant about that here. Just wanted to note that some players might be put off after being overwhelmed with all the stuff there is to do.
3) The combat system is something I have yet to understand. My first contact with it made me laugh though - I'm just building stuff, pressing end turn and boom - a megalodon starts shooting at my hub from like a 10 tiles range. Well, this game has dolphines shooting fracking lasers around. I'm loving it already!
So those were my first thoughts on the game. I guess that to get a hang of it I'll need to play remaining acts when they are released. Cause at this point it's still quite confusing.