I love my C-springs. If you wanted anything stiffer than them, I would go to a coil-over set-up.
I'm using Mach 1 shocks and struts and they match up great. I'm not running caster/camber plates, although I am finally going to get some here soon when I do a few upgrades.
If you're currently running a stock suspension, I would save up and get a bullitt or Mach1 kit that includes springs, shocks/struts and sometimes sway bars.
Pictures of my car can be seen by clicking the link my signature.