I still haven't heard which three teams were profitable. The Sun in 2010 were the first W team to turn a profit, so I assume they're one of them. Don't know about the other two. The Sun are in a unique situation, but the other two may represent a model other franchises can follow.
I have no idea where in Iowa you could put a team in a summer league. When it's cold in Ames with nothing to do, a WBB game sounds good. In the all-too-short summer in Iowa City? No way. Louisville, maybe, but it's a college sports town that practically gives tickets away. Without a profitable NBA franchise or rich athletic department to support it, that's not a sustainable model. Agree that Nashville could probably sustain a franchise, though I'm not sure what facility is available. Maybe Memphis?
Assuming roughly equal costs for most of the franchises, profitability would require strong revenues from game attendance (a function of both volume and average ticket prices), game broadcast revenue (national broadcast revenue is most likely better for the better teams) which would include radio and local TV, and "other" which would include advertising, sales of non-game related goodies, etc.
I think the teams best positioned to achieve solid revenue would be Seattle, Connecticut and Minnesota, based on both their success, and what appears to be more competent management, which would be particularly true of Seattle.
Other franchises that potentially could rival those two IMO would be, in order, LA, San Antonio, Chicago, Atlanta, Phoenix and Indiana. A couple of franchises that should potentially be profitable are NY and Washington, but those two need to completely overhaul their rosters and management, IMO.
Tulsa IMO is very unlikely to ever be profitable.