Just some opinions on some of the ships I've used, mostly about the ones I like:
FIGHTERS:
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Wasps:
I quite like them despite their fragility, and actually prefer them over the Sparks for their faster replacement time and more constant PD damage.
Xyphos:
I never felt they were overpowered in my usage of them, but I mostly use them with Converted Hangar. They don't contribute all that much to damage, but they do help mitigate ship damage a little when their EMP successfully disables an enemy ships weapon and their PD isn't too bad for the occasional incoming missile. They're also very expensive (23 OP with Converted Hangar). I like them because they tend to keep crew casualties to a minimum on account of their durability, long range weapon, and that they must be within close range of a carrier. I would in fact prefer it if the Xyphos didn't migrate at all to other carriers.
FRIGATES:
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Wolf:
Good not great, would be nice if they were useful all through the game, but this will hopefully change with the new skill system changes.
Omen:
I originally thought these were too cheap for how good they were when first playing 0.9a but have since changed my mind in 0.9.1a. They are still however excellent, and I still made use of them during my last play through. I'm I always impressed at how much damage these little frigates can take with their superb 360 degree shields and their EMP attack is reasonably effective against exposed hulls.
Tempest:
Didn't like the changes that were made to the ship at first, nor the increased cost initially, but grew to really enjoy this ship in my last game. I normally give AI full control of my fleet only occasionally taking control; but I had so much fun piloting this ship that I found myself taking a more active part in battle. Even invested precious Character points in Helmsmanship & Evasive action to further improve my experience with this ship. Without a doubt my favourite frigate.
Ox:
I found it too expensive and slow for what it is meant to do. In the End I just build in Augmented Drives into my Capitals if their speed was slower than 8 burn (Paragon or Onslaught). I think the base maximum burn speed of the Ox should be increased to 9. With the ability to build in a couple of hull-mods in the future it should become pretty nice with the Augmented Drive Field hull-mod.
DESTROYERS:
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Medusa:
Have never found a place for this ship, as I've don't seem to be able to put together a load out that I felt did well in the AI's hands. Visually it is a very nice looking ship, but I would like to see it get a massive buff to it's overall OP so that I could experiment more with several different hull-mod combinations. As it is, I don't have much breathing room to try out even a couple of hull-mods without sacrificing Capacitors or Vents.
Tarsus:
Yep agree that the buffalo isn't currently a worthwhile consideration when placed against the Tarsus. The old version of the Buffalo had a base speed of 9 while the Tarsus was 8 which meant you could choose a more vulnerable Buffalo for better campaign map burn speed or a sturdy Tarsus to have a better chance of escaping when caught by a hostile fleet (Although I just realized that with the Tarsus's 12 additional OP, you can squeeze on Augmented Drive Field for 16 OP, only coming out 4 OP less than the Buffalo, so perhaps that wasn't really so much as an advantage as me completely overlooking that with the Tarsus!).
CRUISERS:
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Falcon(P):
Absolutely fantastic missile boat in the AI's hands with an appropriately skilled officer. I'm pretty hopeless with switching missile groups, but the AI seems to be very competent with this ship, and I find it pretty satisfying just to watch the AI pilot this ship. On top of the base Falcon it has two expensive hull-mods built in making it the fastest Cruiser in the game unless you are using the Aurora's Plasma Jets (Although it must be said that while Plasma Jets have a higher top speed then Maneuvering Jets, they don't stay active as long).
Apogee:
My favourite ship in the game (although I'm quite fond of the insanely powerful Paragon as well); Low OP cost, great shields, fuel efficient, good amount of cargo space, a decent sized fuel tank and built in Surveying Equipment; the perfect ship for the intrepid explorer.
CAPITAL:
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Onslaught:
Mostly I keep with high-tech ships, but where before I had an outright aversion to them prior to 0.9a I'm slowly warming up to them. Much prefer the XIV version; not just because of the stat buffs, but also because the Orange and Black colour scheme looks really good on it. Currently I feel a little bit OP starved and wouldn't mind a buff to the amount of OP (I install all of the hull and armour reinforcing hull-mods), but being able to integrate a couple of hull-mods in a future version will help here.
Conquest:
Yesterday: "Why are the shields so crap and why does it have such pitiful armour!", I never gave this ship a fair try, completely ignoring it since I was so focused on how fragile it appeared on paper. It was only on taking a second look, that I noticed it's Paragon level Flux Dissipation, went "hmmm..." and wondered what I could do with that. Several hours later after coming up with a configuration that worked well in the AI's hands, I think I'm beginning to understand why it is liked despite it's weaknesses.
Paragon:
Seems to be the most powerful capital ship in the game. Incredible durability and range. Under AI control and in tough battles (remnants or fully upgraded starbases) it can be a little nerve racking to watch, although while I'm not much better than the AI, piloting the Paragon definitely makes me feel powerful. I can easily imagine many a Paragon captain succumbing to hubris while commanding this technological marvel.