You do know you can claw a controller, right?

So Cuphead's controls suck because you couldn't map some of the buttons on the controller? I played the game on a keyboard and thought the controls were excellent. Simple, the way they should be, but can exploited by some of the more skilled players.

You do know you're not supposed to need to, right?

If you re-read the control layout I suggested, you don't.
It is there if you want it.
I also gave a alternative that does not require players to do this at all.

The controls are basic given the genre of game - and you can customize them to your preferences. I don't get the complaint.

Or you could play with the intended lay out and remove all clunkiness altogether. None of what you're suggesting is superior to the way the devs designed the game. Your suggestions aren't good ones. They all create problems in execution that Cuphead doesn't have to solve a problem Cuphead doesn't suffer from. Having to both jump and aim with the same finger with far inputs with completely different ways of interacting will always be clunkier than gliding your thumb across two face buttons or resting it on both.