Swaybar is stock. I ordered some black 17mm Polyurethane bushings from http://www.summitracing.com. They bolt right on, I suggest a ratcheting wrench, even with that it will take quite some time as there's not much room to work.

Part of the reason for stepping up on the Rotas, is they sell for the same price used as they do new. When I get rid of the Aveo, I can get my money back on the wheels.

For chassis stiffness, try driving a Mazdaspeed 3, or something that actually has a built chassis and you'll understand. Back to back driving with the Aveo and a Mazdaspeed Protege made it very noticeable.

Don't worry about brake bias by upgrading the fronts, it dives so much as it is, even with the H&R's that the backs are more likely to lock up than the fronts anyway. In fact when it was stock, the rear would lock before the fronts which made it a little dangerous. I don't have ABS btw, not sure if you do.