Fighter: Tough call, but probably the Epee. Looks nice, but don't sneeze on it. Including Kilrathi, definitely the Salthi. Like the Epee, but even worse.
Bomber: Scimitar from UE. It may be rated as carrying torpedoes, hence, a bomber, but it doesn't have any!
Capship: Caernarven, big, bulky, underpowered, and underarmed.