easy ride on Mull from Salen along the side of Loch Frisa, turn left then around Loch Torr then up to Glengorm Castle(also diverts to Dervaig). Easy on a tourer or gravel/cx. There’s a few alternative options on this route too if you look on an OS map, up through the pass instead of along Torr. Turn right out of Frisa and 100yds on the right go through forest gate. This is a nice route if you’re a couple or family. Places to stop, not much steepness and a castle at the end of it with standing stones.
Medium ride on Mull from Glenforsa Hotel, cross over to Glenforsa Estate and up to the bothy. The track carries on over a fence and you can head down to the river or carry on. The track vanishes here and gets a little tricky without navigation but it brings you out onto the main road on the opposite side of the island. To the bothy easy on a cx/gravel/hybrid.
Hard route up Ben More, lots of pushing, steep but a mad way down. MTB needed.
There’s an off road route along Carsaig too but it’s super boggy. I was up to my knees and stuck!
The roads are good around Mull with some not much travelled routes and steep sections.