I agree it will be either Cochran or Williams. Even with all of the recent changes, WGN has done the afternoon-to-morning progression ever since Wally Phillips.
But if new management is going to start moving away from the tradition of WGN Radio of years gone by, they might then consider a certain market veteran who would keep or bring the 35+ audience they carry in the morning and would actually fit the format. That would be John Landecker. I'm sure many posts will follow that it won't happen, and it probably won't. But Landecker being able to take calls, be serious one minute and show his sense of humor the next, and discuss movies and show biz without having to play a song every 10 seconds, would fit where he wants to go.
But again, I still don't see WGN breaking away and bringing in anyone not currently on the air there.