Suspension upgrades ,the best route

Well if you want a one stop shop, I'd go with the RMS setup front and rear. That's if you are set on running C/Os. There's nothing inherently wrong with the stock style suspension though, a cheaper alternitive would be to get the Hotchkis TVS, some nice torsion bars from PST or FirmFeel, and upgrade all the bushing to a polygraphite style.