Subframe connectors and control arms

Yes, Lower Control arms especially make a heck of a difference. Just do a little research on what brand you might want to get. I have heard that the Pro3i arms are great. If you are driving the car just on the street, it would be ok to just keep the stock upper control arms in. You don't want polyurethane bushings in the upper arm, they will mess up the spring rates in the rear during cornering.
 
I have Steeda UCAs and LCAs and MM full length subframe connectors. These mods made a huge difference on my vert along with the strut tower brace. The car is a lot more solid in the corners, there's no more movement in the rear axle, and I don't have wheel hop anymore. I'd say go for it.