Due to the open world nature of sor2, big quests will need a revamp. I suggest that you need to do a total number of tasks for the big quest.
Examples:
Cop: get a thousand marks
Assassin: silently assassinate 100 people (includes witnesses)
Gangsters: kill 100 rivals
Slum dweller: pay 1000 dollars at atms
This will grant you the character’s super special ability and an extra outfit for them.
Outfits include:
Clown (comedian)
Donald trunk (looks like an humanoid elephant) (politician)
Upper-cruster (slum dweller)
Sushi chef (chef)
Waiter (courier)
Purple outfit (both gangsters)
Hitman (assassin)