Southwest seems to do well with just 737's which is 4x the size of B6. Plenty of room yet for B6 to grow without needing numerous aircraft types.

If B6 is looking to simply serve more cities than anyone else, then yes, they'll need a different plane for longer range destinations.

However, if B6 is looking to expand in a smart way, it would build up the cities it serves first. Many cities now have just one or two flights a day. How about building those up first?

It comes down to that too much of B6's prior growth has been built on expansion of new cities instead of growing existing cities. Given reduced load levels, that seems to indicate the "JetBlue buzz" seems to fade after awhile instead of increasing. That is why new flights to existing cities don't get announced nearly as often as new cities do. Heck, with many transcon destinations, they've been reducing capacity.

B6 has lots of room to grow with what it has now; fix that first. But make no mistake about it, B6 has hit a wall. They showed up in numerous cities and got business. No biggie there, just about anyone can do that. But how about being the #2, #3, #4, or #5 carrier in numerous markets (markets, not airports)? Now, that's a goal where B6 can say they've been truly successful in a market.

We're in the midst of a transition at B6 from high growth to smart growth. Can they make the change? Time will tell. I bet the change will depend on what they do with their existing fleet and not on introducing a new type of aircraft.