Now let's do the sorc 9/warlock 2
To match the control of the Level 11 Battlemaster (5 d10 dice, GWM, Crossbow Expertise, Heavy Crossbow, Max Dex) you need to use 2x level 3 slots targeting 3 enemies and 1x level 2 slot targeting 2. That also takes up 3 of your 18 actions, you still potentially...