a "rally car" is not a DD...cuz by its very nature a rally car needs to be somewhat disposable. it's part of the learning curve, as you work up to going faster and faster at rallyX or "brisk" TSDs, well let's just say that sooner or later the car is increasinly likely to go home on a trailer OK? and a DD on a trailer is Bad News.
now a DD that has some mods to make it more fun on rough back roads...now we talking!dead stock GC OBS suspension is a great starting point, mebbe do some GR-2 struts, good stout tires for dirt/sno (cooper weathermaster snows 195/65-15 or similar) and some skidplates like Primitive or RallyArmor front n rear.
then spend yer $$ learning how to drive better instead of wasting $$ on mods for a car you don't really know how to make the most of yet. Team O'Neil wintr safe course, one-day Rally Experience etc
full disclosure: I work as an instructor at Team O, but there are a good numba of members here that can vouch for the value of Team O trainin as opposed to dum dum carbon fiber bling on your OBS.....Meyagi, Coondogg, RezPunk (another Team O teacha), etc etc