To be perfectly honest if you like dirt jumping and street riding I'd be inclined to go for some decent vee brakes.
The problem with the disciplines you're into is that it's a lot of trial and error involved in perfecting tricks and stuff so you bail a lot and I know from riding dirt and street back in the day your bars always spin a hundred times and this can and (sods law) will result in ripping out hoses!
I wouldn't bother with discs myself, unless your gonna be riding in the wet a lot or doing BIG downhill runs and stuff, in which case vees won't really be up to it.
Also, MesaMan you mention that you spent a fortune on the wheels so you could run discs... But if you're money conscious why did you buy pricey stuff? You can pick up front and rear disc wheels dirt cheap! Some real good quality ones too.