I will point out that removing a player for two minutes at a time is already the standard penalization scheme for one major sport, so it's clearly not that terrible a frictional problem.

That's where I got the idea, but the penalty box triggers because that player did something. If I grab the snitch that expels one of the other team's players, somebody has to make a decision which player, and then they need to leave the field, and so on--and if the benefit only lasts as long as I'm holding the thing, and I let it go and grab it again, what does that do to the time they're out? And so on. I don't think that's a workable idea, but it might suggest other ones that do work.