Most of U7 and even U6 before and even after hit was eliminated all grouping up to take jiren on would honestly be a pretty good plan, SSB goku at least made jiren know that he can't just take a hit in that form and can be taken off guard because of KK, add vegeta to that and you might get the near end of the zamasu arc, add frieza and now were cooking, add hit and jiren is gonna have some trouble concentrating.
Add 17 and jiren is looking to be in actual trouble, add gohan and somebody's sweating, get caulifa and kale in there and we got a real match.