Depends, I just like getting away -so for me any FSR that is little traveled is interesting. There are some old mine sites and old Minto townsite on Carpenter lake, Minto is generally under water but the lake was way down this year so you could actually wander around.
I have passed through that a lot the last 5 or 6 years, figured I spend a few day poking about. If you have never crossed at the Big Bar river ferry that is interesting, river powered cable ferry but you are 90K up the FSR to get to it.