Lower the rear at least so it doesn't look like a 4-wheeler. I purchased the purple-tagged SS/SC rear springs form crateenginedepot.com and it lowered the rear 0.25" -- makes the rear wheelwell look more like the front. Or you can get some aftermarket springs to drop it more....if you're into that. There are lots of accessories from GM (checkout crateenginedepot.com and click on "cobalt/G5 performance" on the left side of their website and checkout what's available) and aftermarket is coming along too -- check the sites that support YourCobalt, like ModernPerformance.
How much time does it take to install the new springs? Is it very difficult or how experienced should i be to mess with it? Im an engine guy, ive never really messed with suspension. I guess i should start though since the two tie in so close together.