If you can't find something to suit your needs in Pisgah then it probably does not exsist. There are hundreds of miles in Pisgah forest that are open to biking to try.
Other favorites of mine are Tsali and Bent Creek outside of Asheville close to the NC aboretum. Bent creek has some nice downhill runs but not any big drops. Tsali has trails with burms which will put you in flight if ya got the balls to hit em at speed.
Just do some exploring, NC is full of great mountain biking.
Sam