The dragging things into the slots of other things with timers and stuff reminds me a lot of Cultist Simulator. Much like Cultist Simulator, discoverability was really rough past the first few dozen minues, but if a game like this became popular I'm sure people would build a detailed Wiki for to share discovered recipes.
As far as things to fix, I'd say making the stack splitting render the hovering copy with the number of items so that you can see what you're doing would be nice, at the moment you can't really tell how many items you're holding but the issue was largely reduced by often not caring how many items I was holding...