Overall I think this is an interesting game that, with some tweaks, could be wonderful. With no tutorial, it only took me one failed mission to understand everything about the game. (I will say, a tutorial level would probably make it more accessible to people who haven't played an RTS or MOBA before.) That speaks to a simplicity of design that I really appreciate. The enemy design is simply fantastic, and learning the strategies to kite or dodge enemy attack patterns is very fun. I also really like that your attacks are projectiles as well, meaning that they can be blocked if you aren't careful. The overall look of the game is gorgeous, though by the midpoint I was starting to feel like the procgen was showing its seams a little bit.
I think the game could really benefit from some anti-frustration mechanics. For instance, take the choice of whether to build an auto-harvester for an ore node with 29 ore in it. Since the extractor costs 25, this deeply cuts into the player's income. Thus, you have to spend a good amount of the game doing not much at all, since the harvester crew type is easily the least interactive.
I understand that the systems exist to urge players not to invest everything on one planet; you need to get in, and get out, not try and hold out forever against the enemies. But if that's the case, why have the engineer class at all? I have thus far not encountered a time where it felt like building a turret or harvester was the correct choice, which is sad, because they seem like such an interesting part of the game. (It's entirely possible that once I buy the upgrades for them, or if Ore starts being more plentiful, I'll find them more useful, we'll see.)
My first thought, and this is not playtested at all, is that I would allow engineers to "salvage" a building, returning ~80% of its cost. That way, putting down a building costs 5 ore as long as you can defend it until you scrap it, which makes them much more economical. So it's expensive to use turrets as a sacrificial piece, but if you can ensure they survive, they're worth it. This also has the added benefit of making extraction exciting; if most of your Ore is tied up in buildings, you need to hold out until you can liquidate your investment before you get offworld.
I'm curious about your thought process for some of the upgrades. While there are simple health and damage upgrades, other upgrades completely change how the classes are played. The medic upgrade turns them from a slow way to recover after a fight into a valid choice in the midst of battle, which was really interesting.
Overall, I think this is a neat game! Thanks for being a part of the racial equality bundle; excited to follow your other games in the future!