First thoughts before coffee....
If you can't swing a bush hog around a corner, you might fit with a flail.
Plan your trails to be wider than your tractor, and equipment. They're going to grow in on you faster than you think. They will encroach from the sides faster than growing in along the ground obviously, so normal mowers will not really be able to clean that up. I'm faced with rhododendron at my place, and we don't have any equipment to hold it back other than chainsaws, and muscle. You can do it, but it sucks.
As for a rake, blade, disk, or whatever, my ground would laugh at that in eastern PA. We're all rock, with just a hint of dirt/leaf compost across the top through the woods. Even if I could get those implements to work, that would just open us up to a lot more erosion. We're at the foot, and ankle of a mountain, so when the water starts coming down, it's going to have some energy behind it. If you can get ground cover to grow, and just keep it cut down, trails are going to be more comfortable. Once a decade or so we have to go through, and clean up the relief cuts on the trail edge to let water off the trails. If we do that, then the trails generally stay ok. Our ground cover is ferns mostly, and I just let them grow. I just got a flail myself, so I might try knocking them down to 8" or so, but not flat. I'm done messing with briar/pricker... My father just left it all alone, and now that I've taken over, they're getting dealt with. They get scraped off at the ground with the loader, pulled down from the trees with the loader, crushed with the loader, and pushed in. They'll dry out over the winter, and I plan to go back with the loader, and keep crushing the piles down to hasten their decomposition.