Vorlons over powered? Not really, especially in campaigns where the complete lack of a skirmish level and only moderate level fighters as the sole priority choice hampers them in small games. Yes the Heavy cruiser is a leathal piece of kit, but at armaggedon level you would have to roll a game weighing in a either war or battle level to be practical.
In a strictly average roll of 5 points of raid, your looking at either one light cruiser and a transport, or a couple of destroyer and a transport, and 5 transports isn't that scary really.
Boresights are attually good weapons, since you only need to take a few initative sinks to make good use of them, and fighters even with the new anti fighter rule are still good solid damage dealers (especially tough ones like thunderbolts).
Point for point Vorlons are not better than the younger races, but they do start a lot higher on the priority scale.