Movement speed is really king os using your time effectively. I can remember when I first started farming Karazahn, It took about 22-25 minutes. I then built a speed set, which took it down to under 15 minutes.
So the key factors are movement speed, instant cast AE (preferably at range), the ability to take on some tougher opponents in more recent expansions (without legacy damage) and the ability to reset combat.
BM Hunter is by far my preferred option.
Second has to be druid because it has some unique advantages, like the ability to efficiently reset dungeons. Plus it has a tank spec and can stealth.
Still, for straight clearing, having a pet and various AE abilities (multi-shot, various cleaves) is my choice.
Monk has Roll and Spinning Range Kick but it’s not at range. Similar for DH.
Druid top because it can port out and back
Monk 2nd for the same reason, but cant go stealth and is slower.
Shaman, hunters amd locks are fast, but no port so pick vulpera at least
They all work if you’re talking older than one expansion. I keep twenty characters at max level and only really “play” two or three in current content. The rest are for farming runs for mounts, professions, etc.
This expansion I farmed the mounts from Underrot, King’s Rest, Mechagon, Vortex Pinnacle, Freehold, the Hounds in Antorus, Red infernal from Guldan (I had the mythic drop one from when it was current), and the one from Mistress in Tomb of Sargareas. Of course, the real driver was to farm the Love Rocket which finally dropped for me on the 143rd attempt of this year. =)
All were easy enough to solo quickly by the time I had season 2 PVP gear and I had surplus conquest from playing games on my main to send boxes to them. My lineup was:
8 warlocks
2 paladins
2 mages
3 hunters
1 each priest, shaman, druid, death knight, and warrior.
Rogue can skip trash and has sprint so def a rogue
Druid for same reason as rogue
Monk
Dh is good and so is warrior i dont think one js better then the other.
As farming old content is something i do alot skipping 5 sec pulls adds up so dont sleep on stealth. My rogue and druid always clear content faster then my other characters and ive been farming raids and dungeons on all classes. Trust me
i’m not too familiar with lock spells but what spec can you recommend? from what i’ve tested they dont have a good aoe spell i can use when i want without generating some resource first.