Hey, I did couple of loops, it's very easy to level up and to be unstoppable killing machine, I think that by 5th loop enemies couldn't approach me at all. Plasma can be upgraded only to level 4, even though you can still select it to upgrade. Also the pattern the orbs are staying is weird, should it be like that?
Teleporter to spawn boss enemy is moving between loops, I think it's fine but it spawned in the air couple of times, one time in a very awkward spot and at the end spawned probably outside of a map.
Got pushed into the terrain by the moving platform and there's no way to escape. Enemies still could't touch me though. I saw one enemy going fast left-right just above me, I guess you're using basic pathfinding, something fancier could be much more fun.
I have to say that autoattacking makes it dull for me, but I'm a little allergic to vampire-survivorlikes. In that sense I don't really have any advice other than making more enemies, making them more aggressive, adding more upgrades and after that... it might still not be that interesting.
Another idea, if anything, going full-customisation mode might be better - scavenging for parts of the equipment, having weight limits and size limits for different weapons, improving these stats to install more mods and so on. Satisfaction from building your own mecha suit and then unleashing it onto the hordes of enemies can be much more appealing, after that killing enemies is just a test of your build and I know for a fact there's plenty of people craving just that.
So yeah, ideaguying and backseat-talking aside, I'm looking forward to see how the project progresses.