Commuting seems to be pretty easy. Provided you are offered a job and are assigned the E170, you will not have a problem holding CMH. It is the most junior base on the E170. Crew Planning is having a hard time finding FO's to be based there. Now, Capts and FA's is another story, WAY senior. I'm not sure how CMH E145 base is.
I will have to say the best lines for now seem to be in ORD for Commuting. I have a 1600 show time on Tuesday. With that said, I still bidded and will be based in CMH starting OCT 1.