Vegas is also not in the middle of the country and is a bad place to connect passengers through. It is very price-sensitive for most passengers meaning lower yields (hence Allegiant's success there). Not at all the type of market JetBlue likes to get in.
Today's analyst briefing reiterated that the company really, really, really likes O/D pax and not connecting flow. To me that means minimal chance of a mid-west hub any time soon. Greater presence, yes. But not a hub.