This is what i have so far

Act 1- 1 mini-boss( round 3), 1 boss round 6, no drops ( only recommend doing when you have a new character to get the basic rare-epic clothing set for more damage in later quests)
Act 2- 2 mini-bosses with one more boss with higher hp (round 3), 3 mini-boss and one major boss ( round 6), overall drops are rifles lvl 50-75, daggers, and swords
Act 3- 2 mini-bosses (round 3)
Act 4-
Act 5- 6 rounds, Only one boss( annoying to kill, fast dodger) , drops nothing (please add a drop)
Act 6- 6 rounds, One boss, stationary robot at mid, drops lvl 50-75 rifles ( just a guess, did it once and dropped lvl 50 Dual Rifle X)
Act 7-
Act 8-
Act 9-One round, one boss. Drops Shcrider's magazine satchel( 10 rounds in one) and the best Machine guns (singles and dual handed)