Tweaked my settings some more and adjusted some stuff in my video card options, plus setting flora off in the world generation options and I managed to get it to run at ~15 fps at 1920x1080 (with every other graphical option disabled or set to the lowest) which is.... still not that great, but at least I could play around with planets a little bit.
Easy start earth starts you off under attack, as in there's an enemy drone already incoming when you load in. I kind of wish they gave you a little more time to check the base out or something before the attacks started (yeah I know you can disable drones in the options), but I guess it's not too bad since the base turrets managed to kill it before it could do too much damage, and you also start with a halfway decent fighter ship.
It's surprisingly fun fighting off drones and trying to salvage bits and pieces, or drop whole wrecks into your grinder pit. Shooting the drones and watching them crash and explode is pretty funny, and flying around in gravity is just different enough to keep it interesting.
Ultimately it feels a little too hectic for a single player though, because the drones just come in too fast and you have to spend all your time blowing them up so there's no time to try and find magnesium to make more ammo or build a better attack ship to actually blow the enemy base up (attacking it with the starting fighter was a dismal failure). I imagine it would be really, really fun with 2 - 3 players though since you could take turns flying the fighter, salvaging wrecks, repairing the base, and building new ships.
Other than the FPS issues I'm actually rather impressed so far, it's like a whole new game and I haven't even tried to build a rocket to get into space yet.