Some Teams Best Shared in the Big 3,..and Five ...that I can think of anyhow... .

I believe poised to expand (geographically) as a franchise.

NFL:
Jets      Damn near anywhere:  L.A., London, Portland
Bears   Omaha of the Midway
Rams    anywhere out west really
Raiders  Anywhere west coast, even Las Vegas
Saints     New Orleans and Louisville share a river highway.
Jaguars  I wouldn't care if they packed up altogether.  There's that eastern metropolis called Toronto.

NBA:
Grizzlies   w/ St. Louis?
Jazz
Pelicans   w/ a namechange and a move to Louisville, also.  Or Nashville?  Wouldn't the New Orleans and Nashville Jazz be nifty?

In terms of popularity, I believe most desired would be the Celtics and Lakers. Some would kill for this.  I would salivate of the thought of the Cincinnati Celtics.  I wish the Jazz moniker would go to New Orleans and maybe have the Salt Lake City Lakers, freeing up a franchise to go back to Seattle or some such.  Wouldn't the Clippers be a good share for Seattle?  I also made a post of some international sister cities for these franchises (but have yet to make a full list).

MLB:
Indians   w/ Indianapolis?  The Engines?
Pirates     Columbus?  I would love the rivalry and hate with the Indians and Reds.
Angels      with the city of Sacramento's northern California abode
Athletics   with Portland
The Rays of anywhere else.
Astros of Austin.  And Rangers.  If San Marcos would build a 35k seat gem for central Texas, including San Antonio, have both teams park here periodically.  Drive a thirst for market.

 
NHL:
No offense to Arizona, but you're in Arizona.  I'd like some Westside Coyote action for Portland and Seattle as well.  While we're at it, an appearance or two in Las Vegas would be a helluva "home" camp stint.  A Great Lakes Milwaukee franchise should be in existence before Miami.  Let's just go with the Florida Lightning.  Nashville, share the south with ATL.  I'd have to shout some love to the land up north and let them have their Toronto2 and Quebec City or whatever expansion.  I would love for the C-Bus B-Jacks to roll into Cincinnati like a quarter of the time for camp, even sharing with Cleveland if I had to.
I feel that MLS has a way to go across the map already.  And yes, I'd love the same C-bus situation for Cincinnati again for the Crew.

Obviously, these are my prejudiced views.  But as prejudiced as I am, I've never mentioned moving or sharing the Cardinals of St. Louis.  Or the Squeelers.  Nor do I dictate to rename the Browns the Land o' Lakes ButterBrownies.  I love to hate.

See more expansion and relocation talk for football, baseball, basketball, hockey and soccer on my blog (starting in Feb 2014, see table of contents/archive):  Major League/Pro Expansion <CLICK> http://prosportsexpansion.blogspot.com/ 
And please feel free to contribute your two cents with mine.