There eating speed is a bigger limiting factor then grass regrowth. Grass regrowth can be boosted by putting another layer of grass with a 1 block layer of air under the grass field the sheep stand on (wich I have in my setup). To add to that, free roaming animals tend to clutter into corners, wich limits the available amount of grass blocks to eat. By incasing them into glass they are perfectly centered on a single grass block while allowing the surrounding blocks to be grass blocks for faster growth.
Additionally, the autonomous activator allows for shears with fortune, creatly increasing output.
But most importantly: fun. Plopping down annything MFR related is simple, effective and boring. Doing it like this adds challanges, how will you shear em? How do you repair the shears? How will you collect the wool? How will you maximise grass regrowth? How will you maximise sheep eating speed?(IE: water with a piston gate to collect the wool causes the sheep to jump) Its fun tackling these challenges.
TE based treefarm annyone? I got one fully functional without requiring bonemeal
Just not quite happy with the design yet