lol I drove the TJ before the JKU. That was bad.
If you don't like the speaker outputs you might try upgrading the speakers. We went to marine grade speakers in the TJ but we also changed the head unit. Way easier to do that on the TJ than the JK of course, esp since you have Navi. I don't know how much power gets put out to the speakers, just a thought.
Black 2011 JKU Rubicon/ 6spd w/5.13 gears/ 5.5" RK X-Factor Mid Arm (3.5") Springs, RRD Shocks/ Poly Inner/Outter Sleeves and C-Gussets/ Reid HD Knuckes/ 37" Nitto Trail Grapplers on 17" MB72s/ ACE Flat Fenders/ JCR Front Stubby Stinger, Rear Stubby Bumper and Stage 2 Sliders/ Warn 9.5 cti w/Syn line/ OR-Fab Swing Away Tire Carrier w/Fuel Can mounts