Little River Gorge has been explored in the past and re explored in the last couple of years. There are some decent sized cliffs there. Rock quality in the (relatively recent) river washed section of the gorge is good enough to confident solo. I'm unsure about the bigger cliffs.
There are listed climbs up to 290m. But what is listed is likely just the tip of the iceberg.
EDIT:
The big climbs do seem to be rife with loose rock and choss. That would make sense. I've been down their and there is plenty of steep loose slopes. Lower down it is all river wash and mostly solid, but any of the big climb you are probably liable for plenty of choss.
I know a few people who ventured that way if you really want some beta.