first of all i upgraded from a 03 cavy, i know where your coming from.
its like night and day, on the handling doesnt lean as muh and has more control
dont know if it less reliable but gm offers a 100,000 powertrain warr.
im sure at that many miles youll want another car or a newer year one
theres a lot of ways to do it
stage kits or cobalt addiction, intense, and so on
i havent did any major modding , just a few things
other ppl could give you more info on that, but i know its pretty hard considering the balt doesnt take mods as well as other cars do
im sure it could be done