The factory negative camber is like -1.1 not -.5
Setting your camber closer to 0 than -1.1 will make your car sit taller.
If you're worried that your negative camber will wear your tires out unevenly, then get a 4 wheel computer alignment to 0 toe in the front and back. Toe is what eats tires worse than really bad neg. camber.
Actually, if you take it to an alignment shop, with only 1.25" of drop, they should be able to correct most of your negative camber with the stock camber plates. I have Tein S-Tech, with a 1.4" drop, and I had it aligned after installing the springs. I now have .5 degrees of negative camber. The guy at the shop told me he could have corrected it a little more, but that .5 degrees wouldn't hurt the tires too badly, and would give me a little more cornering traction for Wyoming's sh!tty a$$ streets. As far as the rattling goes... the only thing you can do is to go around your car, and make sure that every bolt is tight, and nothing is rubbing, or vibrating where it shouldn't be.