Thorp Mountain 2020
Forest roads to get to the trailhead are fine. Not perfect, but fine as long as you look for and avoid potholes.
The trail itself is quite straightforward - just keep walking. It's flat-ish for the first 1.5 miles then gets much steeper, though never technical. The lookout at the top is neat and if you're not used to hiking in this area, it's a different view of the mountains than you normally see from I-90 (because it's so far east).