"Combos should rotate the ability on a key so precious real estate is saved from all these 123 combos"

Is kind of spoon feeding, it creates no room for error and removes any flexibility from those combos.
Considering that there are very few times in which you want to break a combo in the first place.... there is no flexibility.

I'm also pretty certain that there's very limited error as well. My combos are quite literally, 1, 2, 3/1, control+1, control +2, and 1, 2, control +3.

there's no error there. You just.. don't push the wrong button. Ever.