The other day, I tried to beat ME using only the jump button for fun. I appear you can really beat the game using it exept for some obligatory slide and openning doors or Cel's fight. I think I'm gonna try to beat the game using the less other buttons possible. I don't know if other people already tried it but it's pretty fun to find some routes to avoid crouching and quick turns.

Spacebar only?

yep. Reduce kick, quick turn, action and crouch to a minimum. But it still permit to do side jump, and a lot of skips.

I tried to do a run using only mouse binds (with a mouse that had 2 extra buttons). Casually it doesn't seem possible since you need to use a lot of controls to get through certain parts.