What if Rammus Powerball worked like Sonic's Spin Dash?
You hold your Q to charge how fast you go, with a maximum of 1.5 seconds to charge. When you let go or input a movement command Rammus dashes forwards at his speed but then his movespeed starts to decrease as he runs out of momentum.
If this were to be applied, then he should have ghost active while he is dashing and he should not be interrupted by minions (but he can still hit monsters with it.)
Was just reading another Rammus post when this idea popped in my head and it sounded pretty cool. Riot said that Powerball was an iconic part of his kit that they would keep when they reworked him, so I thought that this would be a good idea when they finally get around to reworking him.