I unplugged my MAF sensor over a year ago (just after I bought my Liberty) and made a crankcase ventilation hose to route the blow-by out of the crankcase and not back into the intake (where it REALLY makes a mess of the turbo, intercooler and intake manifold). I would do the crankcase ventilation FIRST and FOREMOST! That blowby REALLY makes a mess. On L. O. S. T KJ forums, they call it the "elephant hose mod" and the unplugging of the MAF sensor is the "off-road mod". I also have a gutless kitty on mine.
MAN this thing will pull a trailer! I had 8,000 behind mine over the weekend. Pulled it 65 mph on the interstate and got damn near 20 mpg doing it (with overdrive off, close to 3,000 rpm! Before the "flames" start, my trailers ALL have brakes. This 8,000# one has brakes on all 4 wheels. Even with a load like this, the trailer can stop the vehicle.
I LOVE my Liberty. It would be perfect if you could get the 6-speed manual with the diesel.