Here's two things I've wanted to try in traveller but never have been able to yet:
1. making the aslan like the vargr, the evolved descendants of terran felines genetically altered by the ancients. I think I'd like this just to say STFU to all the people who say traveller can't be serious SF because it has "cat people" aliens in it. (BTW, no one says larry niven's known space isn't serious because of the kzin....)
If the aslan were literally descended from terran felines the same way the vargr are altered terran canines, it would end the "cat people alien" crap, AFAIC.
I generally would take the opposite view: not only are the Aslan actual aliens with no biological relationship with Terran felines, but also I have the Vargr being actual wolf-like creatures which evolved on Lair.