For a game this ambitious and of this style, gameplay balance is extremely important, but you scoped too big and didn't focus on gameplay at all. On my second ever run, with zero upgrades from the shop it was trivial to get to wave 50 and I eventually died on wave 64 after a gruelling, laggy 45 minutes!! It's simply way too easy, making it quite unfun, and the way enemies don't disappear after you kill them is bad for two reasons, they clutter up the screen and cover the alive enemies, and sometimes their animations don't stop so they are very easy to confuse for real enemies; and secondly the shear number of enemies lags the game to oblivion. On my first battle the enemies did despawn and dropped a coin, so maybe that's a bug and I just got unlucky, but frankly that still wouldn't have made it fun with how easy it was.
On top of this, the clear use of AI assets is really disappointing, and blatantly against the rules. This game is littered with it, along with really odd design choices. Perhaps you should focus more on honing your raw skills rather than deferring this to AI because the output is of really poor quality below the surface and I'd like to think that wasn't a reflection of your ability.
If this sounds harsh it's because I just sat through a very painful 45 minutes of basically "auto-scroller" gameplay. Testing this should've been priority number one, not an alchemy system and all the other things going on between battles. There's good elements but efforts seriously need to be refocused in the future.