In bang for the buck I would say
1. Decent shocks (KYB's have done well for me)
2. Basic rebuild (bushings, tie rod ends ect). Rubber is the safest bet for lower control arm bushings
3. Front sway bar
4. Frame connectors
5. Bigger T bars. 1" seems to work well w/o too much harshness
6. Offset bushings
7. Or tubular control arms

A level II or III Firm Feel box woul be nice with any of these.