There are some quality of life features from Diablo it certainly wouldn't hurt to copy. The obvious stuff like "clickable weapon text boxes when you hold alt" and "enemy health bars", but also some things like 'when the inventory or stat screens are open, shift the camera so the player is focused in the middle of the remaining side of the screen'. That helps gameplay be less obstructed even with a menu open. An often rather tricky thing to do without some exploits / glitches is to make sure equipping/unequipping items with +stats like +hp preserves your % HP instead of absolute value, so putting on a +2 max hp item makes me go from 60/60 -> 62/62, instead of 60/62. Of course, lots of ways to screw up the coding on that. Could use something on the control setter to warn/stop you if you map multiple functions to the same hotkey.
Also another very important one I noticed- left click lock-on! When you click on an enemy in a diablo game, it will act as if you continue to hold that click aimed on that enemy, even if the enemy moves. For ranged attacks you'll stand and keep shooting at it no matter where it moves, for melee attacks you'll follow it if it gets out of range. That becomes very noticeable and necessary when you have enemies that are moving around erratically instead of attacking, like the goat cultists
Overall looks great! didn't notice too many bugs. When I died and restarted my minimap wouldn't show