I’m not going to go on and say that I’m the mage 1v1 dueling expert, but since I have done some dueling on my fire mage I can tell you my experience. First, mages can win against a lot of classes, but there are some I wouldn’t even bother challenging. One of these is the warlock, I never managed to beat a single one who was decent and armed with equal gear. I’m sure it’s not impossible, but it is really difficult.
As for rogues, they weren’t the biggest of deals. When they open on you you can decide to use your trinket there and then, db and poly them, after which you will gpyro + ring of frost as it hits + gpyro, and this will either force a trinket out of them, and probably their cloak as well. At this point, if you can live long enough for cloak to go away and get a repoly on them after the DR, it is game over for them, you just gpyro them and then combust and get ignite going so they can’t vanish and run. Obviously it’s more complicated against good rogues, but that is how I dealt with most. Most important thing is to not die in a stun. Oh, and if they pop vendetta on you, block that.
Warriors should be pretty easy if you just poly them and then start spamming gpyro. There was only one warrior who consistently managed to beat me while dueling, but a better firemage than I beat him 100% of the time. Shadow priests, not sure, shouldn’t be too difficult. Just make sure to interrupt them while they’re doing their whole build up with a lot of damage (I think you should be able to out-grind them, oh, and if you just spam gpyro they can’t do that much about it). Same with shamans, never had too much trouble. Always remember: if you’re playing fire, poly them, and then gpyro + ring of frost + gpyro, that is an amazing combo assuming you pull it off correctly. And why is it so amazing? Because when the first gpyro hits, if you time it correctly you can immediately cc them again with the ring (needs good timing, like I said) after which you send a second gpyro at them, at which point if they don’t use cd’s then you can finish them off. Reset and repeat.
In WPvP situations you should still be fine as a mage. Most people you’ll be facing aren’t very good, meaning that the match-ups aren’t going to be super tricky. There are some classes I would avoid (warlocks), but assuming you get the right match up and know how to play, you can even 2v1 people with decent gear, which is what I’ve done, without being the best firemage pvp’er out there.
Oh, and if you’re playing a spec that’s not fire, I think your options are more limited. Frost excels at kiting, so try that (frost struggles against ranged). Arcane, I don’t know what they’re good at, never tried them.
PS: realize that this is just something that I wrote as it came to my mind, I did leave a lot out because otherwise this would be an essay, if you want more specific advice against a certain class, reply and I’ll be more detailed. Again, I’m not some rank 1 gladiator fire mage, but I think I can offer at least some useful advice.
I must admit I am in phase at the moment where my reactions are not fast enough. Rogues usually use significant damage on stun before I can react, then they just finish me. I am not sure about Warriors yet but I could die because of gear difference. I can kite them but they also have stun and a few things to close gap.
IF you can get a Greater Pyroblast cast out then it’s great, but with a such long cast time it’s sometimes virtually impossible, with some opponents (especially rogues)