I'll try again and finish this comment once I do... Ok, I lasted up until wave 3, and yeah, your interface works, I'm just used to the interface from Minecraft, and this is a bit different. It's pretty fun, but here are some things you could do to improve the game. Try randomizing the sounds a bit more, I use Godot just like you and I noticed that you randomize the pitch of many of the sound effects within your game, which is a great start, but consider adding a couple more to things like weapons so that there will be an even greater variety of sounds within your game. Maybe it is just because I am new to your game, but I had a tough time dodging all the projectiles and enemies. It's good for a game to be difficult, but make sure that it is still fair, since you don't seem to be designing a rage game =). Some of the upgrades do not feel very impactful, like the ones that increase the fire rate of your guns, but only by 1%. Maybe consider upping some of the stat increases.
That's all for now, but I'll keep testing out your game as updates roll out. I know the feeling of not getting much feedback, so I'll make sure to give you plenty.
Thats true, once I found that pitch mechanic in godot I used it for a lot of sounds. Yes, the sound design is a whole new world of its own, it's actually one of the last things i've dealt with and lost myself in. as you rightly pointed out, there will be a lot of changes there.
Yeah my balancing is constantly swinging between too hard and too easy I'm just trying to get a feel for where the sweet spot is, and I think I've playtested my game way too many times myself which has made it even harder, so it's even cooler to hear your words of support. It really helps me a lot!
As for the powerup mechanic, I'm thinking about redesigning it anyway for the very reason you mentioned because it can go from too hard to too easy very quickly.
Thank you for your feedback!