Finally got my Jeep back from the shop last night. It now has the HP30 I built up (XRF ball joints, Currie HD CA mounts, housing end Johnny Joints, Savvy tie rod flip) as well as a set of Superior 4.88 gears. Evidently combined with my lift and the high-pinion axle design, I need a new front driveshaft before I do any heavy offroading; oh well, I'll call Tom Woods when I get some cash.
Everything on the Jeep feels great now. The steering wobble I had above 50mph is gone; I chalk it up to ball joints. As for the gears, it feels so nice to have power back, I had forgotten what it was like!
The guy at the shop (Steve, at Jeeps Xtreme in Fredericksburg - highly recommended, btw) also discovered why my oil seal had been leaking. The idiots at the Jeep dealership had installed the axles on the wrong sides of the Jeep! There's about a 1/2" difference between the right and left side axles, and when they switched them, the driver side was binding, and rubbed on the bearing. That ruined the bearing and the oil seal. Thankfully, he put them the way they should be, and everything's great now. It's going to be fun trying to get money back from the dealership. I'll be damned if I'm going to let them keep the money I paid them to do it wrong.
God, it feels good having my Jeep back!