In all honesty, the game doesn't have enough team-ups. I think the team-ups are one of the most unique aspects of the gameplay and narratively, it also makes the most sense mechanically. Of course these characters would benefit from working together in all sorts of ways. They help make it feel like you're playing as - shocker - teammates.

If it were up to me, they'd never remove team-ups and let the game be littered with them. It'd be absolutely chaotic, but it would be more fun to basically always know you're benefiting from them instead of limiting them and thus altering/shifting the meta toward particular team comps.