I'm the world's worst at instance and PVP fighting, but don't forget to drop a resistance totem when needed, it helps a little when fighting the dragon.

Also, it may be my imagination, but I find that my flame shock packs a decent punch, and has a nice DOT effect as well, for mobs that aren't fire immune.

At modest levels, I try to buff up a bit for tough boss fights with an elixer or food buff, anything that adds to spell damage. And, of course, a spell damage buff on your weapon, either an enchanter created plus spell damage brew, or flame tongue weapon self buff.

I'm convinced that without overgearing or overleveling an instance, it is WAY easier to progress through using a tank, healer, 3x Ranged DPS combo, even though the tank and healer are mostly excess baggage outside of instances. I'm currently leveling up a death knight as a tank, and although I don't find him as boxer friendly as a paladin, it works pretty well. The really nice thing about a death knight is that you can quickly and easily level one up, without having to do the first 50+ levels, and the constant +15% bonus to run/walk speed is TOO sweet.