OP, the cure to your poor low end torque and drive line vibe is $1000 away.
Get a Bama Tuner with a 93H tune to deal with the low end issue.
While you're at it get an Axle Exchange Alum drive shaft. That will quell quite a bit of vibe AND help your acceleration, and gas mileage. <if you can keep your foot out of it now.
American Muscle will help you out. They sometimes are out of drive shafts, tho.
Your car will be so much more responsive and aggressive, you will have to make an effort to drive smoothly.
`13 DIB, MCA, Perf Pac, Comf Pac, Back Up Camera, MT82, AE Driveshaft, Bama Tune: 93R, BBK Shortys. Borla Touring Mufflers, Air Raid CAI, AM Shift Knob, WeatherTec mats, Stripes and Tint. "Winter 18" GT Wheels and Tires, powder coated black" Redline Hood Struts, Steeda LCAs. Paid Cash.