Babylon 5 Traveller or D20?

some of the other minbari ships, The white star, the vorlon dreadnaught and the drakh clan ships.
The tigara and sharlin are in "warships of", and the white star is somewhere in legacies of war.
The Vorlon Dreadnought isn't statted, I'm afraid - you'd just have to build it yourself using traveller rules (the shadow ship is, so you can take the sizes for bio-lattice armour and regenerating fuel, and obviously MCr value is irrelevant).

The clan ship definitely isn't. To be honest, the stats are "run away".
I prefer the Traveller B5 system as well, although I've found it's handy to have the D20 books around as reference (especially since the Traveller B5 book just cuts and pastes from the D20 books on occasion - especially size classes for starships!). I started doing stats and deckplans for some of the different EA shuttles a few years ago, which I thought would be a low-level starter ship, have to dig them out sometime.