One city I see having sufficient volume for a new club is IND. DL opened a Skyclub at IND near the security checkpoint on the DL side of the new airport and on the AA-US side, there's identical space for an Admirals Club. The combined airline will have flights to DFW, ORD, MIA, JFK, PHX, PHL, DCA, CLT and, if they're smart, they'll add flights to LGA, BOS and LAX. Flights at IND won't be coordinated in connecting banks, but it's obvious that due to its location, it could end up as a de facto hub for some passengers. Same story next state over at CMH.
MCI? AA closed the MCI club as part of its bankruptcy trimming/savings, but perhaps with flights to PHX, PHL, DCA and CLT, it would again make sense.