I have a 12 vert with tune and CAI with 2.73's and am doing a 6.1 with 93 race tune..gears and driveshaft are next. Ive got 19X8.5/19X10 staggered. The wheels aren't going to cause that much of a difference. It actually helped me because I can't break the invos loose like the stock wheels. I would try getting a proper tune for the changes you have made and go from there.
2012 V6 Convertible JLT CAI, Bama 93R tune, Trident Motorsports Axleback
Black Mustang Registry #1119