From my experience, I would not expect to be too successful in trying to get bumped in any of those Comair cities. Delta made contingency plans several weeks before the Comair strike and reduced inventory avaiable for sale. Thus, I would say you are already too late as they know how to accomodate everybody. I did fly some Comair routes on mainline DL this week out of / to Chicago, and the flights were almost full, but not overbooked.
I suggest you look for the bigger routes between the hubs, because many people have to fly there because there is no non-stop service right now.
For instance, I got bumped off the JFK-ATL flight last week...