I have found that the Halifax frigate is my go to on the lower classes for hit and run. Enjoy the defense of the Leningrad 2 for smaller maps without much maneuvering
My new favorite tactic against AI is to have a troop support ship with me, take my first honor frigate and unload marine pods on the enemy ship, and reload more. The ship loses significant power so it doesn't hurt me much, and marines eat away at their crew giving me Xperia!!!!
I think its pretty easy to rack up enough XP to get to a Frigate. I don't dare spend any XP on upgrading my officers on the Corvettes. So for more expendable missions I use my free ship, and try to push the XP to improve my Frigate's stats. Currently on a Firebolt Frigate.
I think with bigger ships like destroyers and light cruisers, its a must to have support ships or wing ships with you. It keeps the faster corvettes from hounding you too hard, and if they do hit and run, at least the repair tender will offset any damage they might pull off by hitting and unshielded side. Then you pin them down when they make a mistake, or corner them and hit them with a high powered weapon.
I've taken a new liking to the Engineer's repair skill, maxing it out on a frigate, I pretty much auto-heal everything before the next round. Even if a ship blows up in my face. Maybe it won't be as effective on higher tier ships, but it definitely works well when you can repair 50% of your hull's worth in one repair round.
In playing against AI, I prefer to power up weapons 2 charges each (so I don't get the expensive yellow) and get the +1 or +2 damage bonus skill, then come close for the extra range damage boost. That way I'm dishing out 5-6 damage per 2 charge laser, so its just as efficient on power as a missile.
So I learned something new today. If a enemy sector is surrounded by your tiles, you can go in there and sit, no AI or enemies can move in. So you can just safely capture the sector after a while.
warlock, team up with an ally to start learning, ask questions in the chat. Most players, on all sides, are glad to help you learn the ropes. Expect to lose your free ship a lot.