So I started an NFL-D.
One D-team will be assigned to two NFL franchises, geographically whenever possible, one for each conference. Here's what we came up with:
Red Conference, Northeast Division
Annapolis Cruisers (Ravens, Skins)
(to play at the Naval Academy)
Hartford Whalers (Jets / Giants)
Frankfort Yellowjackets (Eagles, Steelers)
(there was a team by that name in the early days of the league)
Syracuse Stars (Bills, Vikings)
Red Conference, Heartland Division
Iowa Jennies (Bears, Colts)
(A 'Jenny' is a small plane, in tribute to the Barnstormers team in the Arena league, former home to Kurt Warner. can't fit Barnstormers in the allowed space.)
Columbusaurs (Browns, Packers)
(a Columbusaur is an iguanadon-like dinosaur. there's a Canadian college team wi that logo)
Memphis Nighthawks (Falcons, Titans)
(to play @ the Liberty Bowl. Memphis briefly hosted the Oilers/Titans and had the Memphis Grizzlies in the WFL, and the Mad Dogs, in the USFL I think)
Tulsa Twisters (Rams, Chiefs)
Blue Conference, Southeast Division
Orlando Sun (Bucs, Dolphins)
to play at the existing Sun Bowl. Orlando had teams in the WFL and the USFL.
Birmingham Bandits (Lions, Bengals)
to play @ Legion Field. Birmingham has had teams in the WFL, USFL, CFL and NFL World League
Mobile Marauders (Saints, Jags)
Shreveport Shrimpers (Panthers, Patriots)
to play @ the existing stadium. Shreveport had a WFL team.
Blue Conference, West Division
San Antonio Cavalry (Cowboys, Texans)
to play @ the Alamodome San Antone had a WFL team and probly others.
Portland Storm (Seahawks, Chargers)
there was a Portland Storm in the WFL. cool logo
Albuquerque Dons (Cardinals, Broncos)
(fyi a 'Don' is a term of Spanish royalty, like a Lord or a Mogul)
San Jose Bytes (Raiders, 49ers)
(I think San Jose had a team in one of those alphabet leagues but I don't remember)