With a nice stroker engine which is build for torque you don't need 5 or 6 gears nor steep gears in the back.
The stock transmission or an A518 with a bigblock-bellhousing and 3.23 gears are more than enough for happy cruising.
The Hemi only adds potential 'misery' in the form of a bunch wires, injectors and computer stuff. Sure it will mostlikely get better MPG but other than that probably the only fun-factor is when you open the hood.
With a stroker motor the fun happens every time you press the gaspedal...