Well, STL has 4 runways now, and no traffic whatsoever. The city has over 50 gates that aren't being used at present, and could easily fit E-190s into the terminal space they have dormant.

My vote----STL. TWA had 365 mainline jet flight per day in/out of STL, to over 100 destinations. AA has only 48 jet flights today, to only 10 destinations. AA abandoned it, just like they did at BNA/SJC/RDU; gave away the market share and decided to let some other carrier reap the benefits of that market and make those profits!