[lxndr]

For the rear, something must be bent out of alignment. Had this car been rear ended? The only things that would cause uneven tire wear in the rear would be bent swing arms, bent axle, or bad wheel bearings.

For the front, I've never needed to replace the bearings so I can't tell you if this would help.

My car had an odd clunk/drift in the steering when I first got it. It turned out that the 4 bolts holding the steering rack in place were loose.

There shouldn't be any problems with lowering the front so long as you don't go too low and you get a front end alingnment afterwards. When you lower the front end you will end up with massive toe out.