Hocking Hills is kinda hit or miss depending on how busy it is in the tourist areas. This route is a little longer, but it has some good riding in it. I can't vouch for the northern loop around Columbus, but taking 56 to Athens, then 329, 550, 377 to McConnelsville is nice.
https://www.google.com/maps/dir/Marysville,+Ohio/39.3296255,-82.1283826/39.3522145,-81.8818244/39.6450738,-81.893982/Marysville,+Ohio/@39.8262233,-82.9759548,10z/data=!4m19!4m18!1m5!1m1!1s0x8838c4ceac89bba9:0xc6437f210d8aa31a!2m2!1d-83.3671432!2d40.2364486!1m0!1m0!1m0!1m5!1m1!1s0x8838c4ceac89bba9:0xc6437f210d8aa31a!2m2!1d-83.3671432!2d40.2364486!2m1!1b1!3e0