My opinions:
I. The Size 5 torpedo ships
a. The Gladiator is really under-rated, but, you definitely don't want to operate it singly...given how crappy turrets are now, you would want to have a beefy fighter escort, or multiple Gladiators. In combat/fleet action, I could really see a bunch of Gladiators being effective against the other sides Retaliators, Gladiators Harbingers, etc. Pro's: Carries 4 Size 5 Torps, and it looks cool!....Con's: Smaller Ship, Size 1 Shields, slow easy target, small guns (I used to have a lot of fun back in 2.5/2.6 engaging somebody in a dogfight and then surprising them with a torpedo...only the greenest n00b will fall for that nowadays, lol).
b. The Harbinger is a Vanguard, so it is really beefy with Size 2 shields & components, and carries big guns for defending itself. Pro: you could probably fiy this solo and operate singly in the verse right now & in the future; also has a bed. Con's: only carries 3 Size 5 Torpedoes
II. The Size 9 Torpedo ships
a. Retaliator....god, I love the looks of the thing, and I've had great times with it, but it is hard to recommend now. But, in the future, it definitely could be great again. With 6 Size 9 torpedoes, this thing is awesome! But BIG Con's are: no guns for the pilot, defenses rely on turrets (which are crap) and it is slow slow slow....Max Speed is 814 m/s (but the quantum drive is fairly fast).
b. Eclipse...as long as you understand stealth gameplay, and you can commit to running away if caught, this is a great ship. But you definitely cannot go toe-to-toe with most fighters, at all. However, if you can sneak up on somebody, you are deadly. Be aware that the utility of Size 9 torps against small ships will probably be reduced as gameplay gets refined...since you can only carry 3 torpedoes and can only fire one at a time, you aren't going to be able to take down big, capital ships. The worst Con: the cockpit lighting makes it hard to see out of! Also, no bed...