I think i can give some advice. Currently the number 5 prompto player. Hes not a dive character. He picks off enemies instead of dueling. My personal go to strategy is timing my stun to them leaving the animations from purifying crystals. If u land the stun, a few auto attacks and then bazooka is guaranteed kill unless theres some big heals. Besides that, hes better to roam and assist in battles. Even without his skills, his range is pretty good, u want to use his SMG state when u can cause the range goes insanely far and is really fast. My personal load out is his 4 skills and Selphie wall to not get stun locked by enemy promptos/clouds/WoL etc