Get the front "blade" sway bar first. It has the most dramatic effect on handling.
Get a range of springs.
Upgrade the servo saver spring (see discussion in the NTC3 thread)
Get the 2-speed (if you don't already have it)
Get THE FIX (again, look in the NTC3 thread, we talk about it all the time) - this strengthens your shock towers and diff cases a LOT.
RC10L2.5W - RC12.4 - RCNTC3(bmi) - TC4 (modded) - B44.2 - plus rent-a-rides! :D