I won't argue that I wouldn't expect the cutters to win (although it won't be quite the whitewash you'd expect). However I'm not surprised, and I don't think that's wrong to expect, for the following reasons.
1)
Actually it's a bit over 6 damage per turn. Not that the average value means much given the way
beam weapons work, and the critical table - on a ship that small a
double damage critical result is usually either 'dead outright' or doing no additional damage.
2)
A
Sho'Kos may have 12 damage but it only has 10 crew.
3)
The Sho'Kos only has seven attack dice, not eight - one of which is in a boresight mount, and four of which are
weak, needing 6's.
4)
I've never been quite comfortable with the 2-for-1 patrol ships as many of them seem as good or better than a lot of the regular patrol ships. The
Tethys Laser Boat is a good example.
5)
This is the most important one, really - the patrol cutter is precisely what the transport is
not designed to fight (multiple swarmy light ships) whilst the transport is about the only style of ship the
Sho'Kos can be said to be well suited to fighting - a medium armoured target with big blind spots in its weapons.
Much of the 'cost' of the transport is the fact that its weapon is a
beam. That means, that like all Vorlon weapons, it ignores armour and
interceptors. This makes it nasty as hell against light craft
with armour and
interceptors (a
Chronos springs to mind) but represents a load of wasted capability against the basically unarmoured
Sho'Kos. So is the
Advanced Anti-Fighter. So is the
Superior Technology bonus against ships with
Stealth. In armament, at least, you can level the same accusation at a lot of Minbari ships; all
beam or
mini-beam weaponry.
For comparison, imagine a
Maximus and a transport trading fire - the escort frigate has more attack dice, a better hull, more hit points, and
Interceptors, but will be taking that same 6.27 damage per turn in exchange for delivering less than 3 damage per turn back. One of which
Self-Repairs.
The Vorlon transport has identical firepower to a Drakh Heavy Raider, which is one of the nastier swarmy ships out there itself.
I don't know, I find it very difficult playing lower priority games with the vorlons, sure a transport is the smallest ship that carries a vorlon but the ships are living/oganic so why wouldn't they have unmanned scout ships?
Why would they make a military unit less capable than a runaround shuttle? And note that the same argument that applied to the Shadows applies to the Vorlons - they don't care about adapting to the younger races.
'Priority level' is an artificial concept - give the Vorlons a raid-level ship that you can fit into a minimum-sized skirmish priority game and you get a better situation; the Vorlons are supposed to have trouble putting together a fleet at that level because their primary fighting ship is a war-priority vessel (much like Minbari or Crusade-era EA).