I decided to play around a bit with Dave's Redistricting again and did a redraw of Ohio based on a scenario where the Republican-drawn districts are struck down and redrawn to avoid county splitting and severe partisan bias like the ones in Pennsylvania. The party margins bit might be kind of off since it's based on the 2008 election. I suspect if these boundaries were used in 2018 it would only have given the Dems all the seats they won by over 10% plus the 12th (maybe the 2nd at a push, but I'm not convinced), although that still means a 9 GOP-7 Dem partisan split instead of a 12 GOP-4 Dem one.