Lots of good discussion in this thread, both pro and con. I'll add a few more cents to the discussion.
One of the more interesting aspects of studying military history is how often some new plan worked in a battle precisely because it had never been seen before. There has been a whole lot of "I didn't know they could do that" moments in military history, and it usually takes one good battle to change the conversation. From that note, I have one key conclusion to draw: it is going to be very hard for us to really nail something like this down. Sample size for games are going to be very small, which means almost all the evidence is going to be anecdotal. It is also overly easy to overly-generalize from one's experiences, a danger in all strategy games.
Yes, choice in a strategy game does imply hierarchy. Some choices will be better than others. But the big problem with comparison is that in theory we want to eliminate all other variables so that we can make a just comparison between the two items in comparsion. The problem is that all other variables are never going to be equal. Players not only make choices between different ships, but also between different upgrades on those ships, different squadron compositions, different admirals, different objectives, different bids. Then when an opponent who has made an equally diverse set of choices for their own fleet sets up on the table, we've got an even broader set of variables. And if we wanted to eliminate another variable, we'd have to have two players of exactly equal skill with exactly the same amount of sleep and food with no past history of being each other's arch-nemesis.
My sense so far is also that almost every game is going to turn not merely on the fleet design but on a major tactical mistake on the part of one or both players. Its that way for chess until you hit the top 10% of players. What I've seen live of both X-wing and Armada seems to confirm that stat. So given that, even if we do have a break down of one ship being just better than another (if only a hair), it likely isn't going to cause them to lose any more if they bring it or win any more if they don't.
Finally, to bring us back around to military history and changing the conversation, we're going to have a changing of the conversation every few months as new units get released and the world adapts to their inclusion.