What I did:
Installed the 2" SLR shackles to gain back my stock attitude (my truck was sitting level). Then installed the new t-bars and my truck was level again - knowing this would happen I installed the AAL on the same day to (once again) get the stock attitude back.
Cranking the torsion bars makes your ride stiffer up front and takes away downtravel, but I personally haven't noticed too much of a ride difference. You could always install the shackles (or AAL) if you want a bit more height in the back and then decide if you want to crank the torsion bars a little to compensate ...