I wish it would close to all commercial ops. ATW and GRB fight for traffic to each of their detriment. They both already (but ATW especially) spill most of their low yield traffic to MKE. If it were just GRB, no doubt there would be even more spill to MKE, but the remaining consolidated traffic would be larger and higher yielding than either station can offer today. It would make some set of DEN, DFW/IAH, and (my dream) EWR viable.

This is obviously pure upside for folks in GRB or anyone to the north. The 20-25min extra drive would be worth the extra nonstops for folks in the Fox Valley. And anyone further south (e.g., Oshkosh) is already mostly flying out of MKE.