A bit late to comment but this is really fun. Obviously lots of small things like missing sound effects, lack of menus and ability balance but not stuff that you don't already know.
You will need to think about is how to better handle your enemy pathfinding. It's way too easy to glitch them into a corner and aoe them down. Also it would be really nice to add an enemy outline when they get too close to something like a tree that obscures them a bit.
I would be careful with going too overboard with the RPG mechanics. I don't see this as a a game i really want to invest heavily into builds and instead just way a quick and easy way to feel rewarded for exploration/progression + a way to make the content easier for myself if i ever get stuck. But yeah i don't think that the builds add too much besides that. The PoE talent tree is cool to look at but i don't feel like it's going to add too much to how the play the game other than just being another thing i need to think about. Does the choice between power+4 or power+2 and 2.7%cd reduction really add to the experience, i wasn't really feeling it.
I think that' less may be more' in the case of RPG mechanics in your game.
Anyway please continue making this, i had a lot of fun. The base of the game is really solid, just be careful of scope creep.