More lead at 12 or 10/2, increases swing weight, raises sweetspot, increases power on ground shots.
If you're using poly or co-poly strings change to a Multi they have more feel and more power but will lack spin.
Service power is more about technique than anything as it's related to head speed velocity more than than mass.
Unfortunately you'll never find a racquet to suit as you want contradicting characteristics,
max power - max control - max service power - best return
still searching: Mrgreen: