You'll go crazy trying to predict schedule changes. Just recognize that they occur - and that those that create a misconnect or >90 minute change to arrival or departure time present an opportunity for a routing tune-up or a refund.
The end of the DTW-CAK services really hoses you. You mentioned you like CAK better but PVG-CLE still has good, time-efficient routings both PVG-DTW-CLE and PVG-ATL-CLE.