This is a completely out-of-the-box idea (because hardly anyone else will use it), but I would enjoy a return-to-center cursor mechanic in the game. As of right now, you have a completely different cursor mechanic, so it's impossible to play this game with a graphics tablet right now. It would have very little impact on the gameplay of other non-tablet players, so it shouldn't bother too many people. The only potential problems I can see would be with controller support, though you could try implementing something to detect the presence of a controller and switch to a more controller-friendly cursor mechanic.
The only reason I suggest this is because I'm more accustomed to playing FPS games with a graphics tablet (sounds weird, I know). If I could play this with a tablet, it would be more comfortable for me. (If you don't know what I mean by 'graphics tablet' try searching for 'Wacom Tablet' or 'Huion Tablet' to see what I mean.)