Thank you for the advice about the Knobstone trail! Its very helpful. We were hoping to do a shorter trail next summer, and were considering this one, but it sounds like it might be a bit beyond us right now. We do plan to thru hike the Ozark Trail in 2016.
You guys hike considerably faster than we do, so I think you might be able to hike Alto Pass to Fern Clyffe in that time span. I strongly feel this is the prettiest and most interesting section of the trail, and would go there again in a heartbeat. We went in early summer, so I don't know if the things I liked the most will still shine, but I'd take the risk.