My offer is simple:
make positive status effect inflicting items! Increased ASI, CTR, resistances to all damage types, damage dealt. Temporary. Like, ASI or damage pills, damage resistance vials ect.
Where there are debuffs, there should also be buffs!

Optional: make buff bomb - object that upon full charge and release adds positive status effect, like damage resistance or increased damage to party for 30-60 seconds.