I liked the way Shadows played even before the tourney lists; they are a "hit and run" fleet, and are really deadly when played as such( although I admit that they are challenging to play at their maximum efficency). They tend to get into problems when there´s no terrain to hide behind, however.
A major problem is that damage table - double and especially triple damage is terribly effective against the Shadows (and, to a lesser extent because of their adaptive armour, to the Vorlons as well). I played an ISA vs. Shadow game recently, fielding a Victory and a couple of Whitestars against a Shadow ship and a few scouts - at the end of round 4, there was not a single shadow remaining on the table, with me not having lost a single ship. While this was in part due to the facts that my opponent made some poor moves and that there was no terrain, all those multi-damage weapons were terribly deadly.
I don´t think that adding more self-repair dice will do the trick, however - they are too unpredictable, and a single round of bad rolling might be the end for your ship already.
The Vorlons are a different matter, however, with their own problems - their main ships are not maneuvrable enough to really be brought to bear on most opponents who happen to come into range, and their transports and destroyers aren´t that effective on their own.
Still, I think that only a few changes would have to be made to rectify most of these problems - my suggestions would be:
Vorlons:
The Heavy Cruiser (and maybe the Light Cruiser as well?) get´s Hull 6 and an additional AD to his lightning cannon only (appropiate, since it is his main weapon; this would also make it a little more powerful than the Light Cruiser´s equivalent weapon). Raise the range of the lightning cannon a little (to a maximum of no more than 30")
The Light Cruiser get´s a 24" range on it´s lightning cannon, and maybe a 2 AD discharge cannon.
Vorlons may use "All stop and pivot".
Maybe the discharge gun could either gain "anti-fighter", or change from beam to mini-beam. Vorlon fighters are no that effective in protecting against enemy fighters, which in turn can become quite a problem for the Vorlons - enabling the ships to better deal with them would reduce that somewhat, without removing that weakness altogether.
Shadows:
Shadow ships get a 24" range and a F arc on their MSB. Raise the damage value a little.
Shadow Hunters get a 18" range on their MSB.
Shadow fighters get eitehr 3 AD or a 3" range on their polarity cannons.
All Ancients modify the damage table - here´s some ideas, how:
1-2: 1 damage
3-4: 2 damage
5-6: 3 damage
7: 3+ d6 damage
or:
1: 1 damage
2: 2 damage:
3: 3 damage
4: 4 damage
5: 5 damage
6: 6 damage
7: 7 damage
or:
table remains unaltered, but Ancients reduce multi damage (reducing double damage to one-and-a-half damage, reducing triple damage to double damage).
Another idea for all Ancients: replace dice for self repair with a fixed number, e.g. 4 points for each die.
now, while applying all of those changes would indeed be a major overhaul of Vorlons and Shadows, I think that using a few of them in combination might possibly do the trick.
Well, as both SFOS and especially the tournament lists have been published in the more-or-less recent past, it is not likely that there will be a change there anytime soon. Still, maybe it would be a nice idea for Mongoose to publish something like an "Ancients fleet book" eventually - that would not only allow them to bring the Vorlons and the Shadows closer to what most players seem to want them to be, but also to bring up those other first Ones we saw in the show and which had those nice miniatures in the B5Wars era.
Oh, and a word or two about the Shadows T arc: Given that Shadow ships are even more maneuvrable as White Stars, they turn in a way comparable to fighters - which also have a T arc. In addition, in the show, the Shadow ships fire forward and downward, striking at targets while passing them by, so the T arc could as well simulate the shadow ships conducting strafing runs against the ships they fly over (pretty much what the current rules allow Shadow players to do - fly straight behind a ship and shoot it when over/behind it).