I Tried (and failed) to get a T-Rex race into our Star Trek campaign instead of the Gorn 8)
Now of course there are a lot of Undefined League races and even older races boardering the Dilgar for instance - if they WERE a race of T-Rex like people (Advanced and intelligent) makes sense for the Dilgar not to attack them.
Or maybe the Raptors - yeah perhaps more likely to be intelligent tool users...............
Another fun idea I and few others played around with was if a refugee group from the 12 colonies was heading home to Earth and arrived in B5 spacepersued by the Cyclons - bit of a two way culture shock - esp since seems to be a lack of machine intelligence in B5 - I think there are AI's (isn't the B5 main computer a Old Centauri one?)
Or if the Shadows were wiped out last time round and Vorlons decided to purge the younger races of bad influences.............like the Centauri!
If the Dilgar had advanced slightly more slowly and not attacked Makrab or ground down the Brakiri homeworld first, they might have been able to hold on to their gains into the period of the show - a Dark Empire glowering at the other races and preparing to unleash Phase 2........
The Shadows are actually trying to get the races ready to fight a Third Space invasion - having recognised that the Vorlons are still under their control and prepring the way for them..............
The Minbari are infiltrated by the Shadows - maybe no Earth Minbari war....The Vorlons are the ones that sleep for centuries - wake up, give a big sigh and try to sort out the mess the Shadows make. Have the Shadow's have a Ambassador but are the opposite of the Vorlons - more likely to give you
and your enemies tech and cool stuff and watch the fun.
ahhh so many ideas........................

:lol: