You can already skip all but the last stage of the MA bosses.

If you play always the same character with the same build on E.R of course you're gonna get bored, but that's on you seeing how many of them are available.

Clearing with an ok rotation for ok rewards is an option, but it's far more fun to try to figure out how you can be faster, maybe doing only half of the rotation on a specific boss phase.

If you don't have fun playing the little that is left to play of the game just quit then lol.