If you ride alone most of the time simply close the passemger A/C vent a little or all the way (same for therear if no one is back there) this should give you more "pressure". If this is really annoying you and you feel like doing some work, disconnect the big hose going under the console and measure the diameter. Go to your local home depot and buy a plastic reducer that will fit inside the hose. This will "choke" down the rear airflow and equalize all the vent pressures. Now be prepared for a lot of "heat" from the backseat passengers who will complain that the rear is not as cold as it used to be and takes longer to cool down.
The design is meant to cool down the whole interior as fast as possible and since you have a bigger rear area (nothing personal meant here) "they" decided to put more airflow to the rear not thinking about the percentage of time the rear is mty while the driver side is always occuppied. Now if you want to "tick" (should not have used that work, it's a whole different issue) the old lady off you could get some additional hose with a coupler and swap the passenger side vent to the driver's side and vice versa. Kinda silly, but could be fun.
When my wife is bitchin or giving me a rash over something, I kinda reach over and turn on the seat heaters, takes about a minuten then she usually gets quiet until she figures out what is going on, then I really get blasted, but I am smiling all the time LOL
Good Luck
\'01 Chevy EC/2WD/SB, T/F 45 gal, Delvac 1, TranSynd, deep pan, MAG drain plug. Escalade handles & painted bumper capto. After market grill, billet bowtie, Stockland cover, no side trim, no juice, no gauges, nuttin but stock! Nicktane Big CAT Pre-OEM. Gone, but not forgotten.
'07 Crew Cab LBZ stock all the way except added 45 gallon Transfer Flow tank and billet grille. Great truck also now gone, but not forgotten.
'12 Crew Cab stock for a few more days LOL