The only thing possibly notable was my own experience when playing the narn. I can imagine, this stuff is one of the less finished work, but at the moment the narn capital classes seem mostly a bit "useless" compared to different classes in for example the earth alliance. I just get the feeling that the research for these ships is just an "addition" to other useful stuff, but not really nescessary itself. Most of the times I play, it is enough to just rely on the first capital ship class and simply wait for the g'quan to come instead of using the the two or three classes in between in the meantime. If the paths in the tech tree would be less "parallel" and more bottom-up, maybe with some more specialization in the classes, the narn gameplay would become more complex and with that- more interesting. Also, just as a question: are vorlon ships meant to use shields? Maybe I completly miss something in the lore, but as far as I know their ships are mostly described using organic armor wich is more regenerative.
The Narn haven't had any TLC since the tech trees were built 2-3 years ago. I'm in the midst of a major overhaul of the tech tree for most races with a focus on course balance. The Narn in particular were deficient in several ways which was making them harder to play than intended. Here is a brief rundown of strengths and weaknesses of the Narn capital ships:
Rothan - short range weapons fwd and aft arcs only - capital colony ship
Rongoth - Short range, all round weapon coverage, excellent at thinning fighters and good against light frigates and corvettes - will not fare well against most other capital ships and heavy frigates.
T'Loth - Good bombing, good short range all round weapon coverage. On review I need to increase the forward arc hitting power.
G'Quan - Long range beam, good forward, L & R short range weapon coverage, decent bombing, energy mine (not available till level 3).
G'Vrahn - Good Fwd & Aft beam, weak bombing, excellent all round weapon coverage (2x L & R), excellent anti-fighter coverage, best fleet brawler.
Bin'Tak - Good Fwd beam, weak aft beam, short range good all round weapon coverage, best bombing. (I need to improve this ship)
The Vorlon have and use shields. There is ample evidence of this from the show, they also have bio-armor and self heal quickly. Concentrate fire and kill them one at a time, wounding a Vorlon ship ensures you'll see it at or near full strength next engagement.