I'd prefer they add a level selector to the patrol maps in the same way as the missions and strikes. That way I can choose my own difficulty for the entire map. Maybe follow suite from DiabloIII torment modes with higher levels have slightly better loot drops (based on destiny's loot style that would likely be better legendary loot and engram drop chance, not actual level of gear). That builds a nice feedback loop with you getting loot, improving your character, picking a harder level, getting more loot and so on. You want the increased loot chance as the better your gear the more likely it's a side-grade rather than upgrade and you want to keep the feeling of progression going.