I figured this out, actually! FloatingPawnMovement will work, I just had to set max speed, acceleration, and deceleration to 99999 - now it will just add whatever force I want instantly and then stop adding that force instantly.
Very good. I feel much better now. It’s nice to have full control of my character’s movements. 
I’m gonna have this guy bouncing on trampolines and getting shot out of cannons soon enough. 