Burchey, the "old" trail starts at the end of the family picnic area, across from the pond and the wooden bridge, and to the right of the waterfall. No signage and not maintained, but clearly there once you wander into the area. Steeper, but it cuts out the North Fork water crossing and saves maybe 20 minutes versus the current trailhead. It joins the MMWT at the JM Wilderness sign.
I'm definitely interested in the others as well.
