1-5 and 2-7 have the highest experience and ally point rate. 1-5 is faster than 2-7 as long as you can clear it and reenter within 45 seconds (requires a faster connection/phone).
43-6 and 45-6 have the highest experience and ally point rate among the 5min quests. I assume 45-6 gives the most BT but can't confirm since there hasn't been a quest BT event since it was released. 43-6 also has the most convenient layout as toonreaper mentioned.