Keep your current lift and get gears and lockers. I have a 5.5" T&T Y-Link lift with great flex, 4.56's and ARB's. The gears and lockers make waaaay more difference than the flex. I just got back from the Rubicon and the rigs with lockers had a much easier time than lifted rigs without. One of the guys in our group had a killer Landcruiser with a 350, 35's and a lift (spring over). He struggled in a lot of places that we just walked through simply because his wheels weren't turning.
I've installed gears and lockers for lots of friends and one thing always holds true: They wish they had gone one gear size lower (numerically higher). Everyone gets locked into this "my mileage will suck on the highway" mentality, which simply isn't the case. In fact, with taller gears, your mileage will be terrible around town and on hills, since it takes more for the rig to get take off. I found this out the hard way. My point is go with one size lower than you think you need.
As for the lockers...I put in Detroit Trutracs in two friends' YJ's and they are awesome. You can get them for about $400 each, they are un-noticeable on the highway (even in the ice) and they lock up great when wheeling. I love my ARB's, but for the price, I think the Trutracs are the way to go (not to be confused with lunchbox-style lockers that replace the spider gears; these are a well-built, full carrier).
Anyway, my two cents...Good luck!