Problem with vorlon fighters is the low speed/bad dodge combo - if you're trying to avoid dogfights, you need to keep your fighters attached to a Transport, as it will dissuade most anyone from coming close to them (assuming you force them to move first) - although obviously Thunderbolts could still quite happily engage them with shooting without fear of reprisals. Problems arise when your destroyer or transport has to APTE, however (which is quite often, especially for transports in order to keep them remotely near to being in range) - the fighters can't keep up.
Also, there's nothing to stop most anyone just throwing long range AD at your fighters. Their poor dodge makes them go poof quite easily.