This is the Pvp part:
[...lots of great stuff favoring Mages...]
Pve:
So far I think warlocks are way better then mages in pve due to fact you can actually stack all dots and then cross shadowbolt. I've literally had no issues in any dungeons that I've did (gave up on locks 1 days into 60).
But seeing as the ignite mechanic is just straight up op, I am fairly convinced that precasted Pyroblast>Fireball>Scorch (talented)>Instant Pyroblast with Arcane Power>Fireblast>spam arcane explosion> can actually deal up to 50k dmg within 10 sec of time (not counting the the precasted Pyroblast).
This is for Pve specc which would look something like this:
https://classic.wowhead.com/talent-c...5052000123-002
I'll soon be 60 so keep watching me and I'll stream BRD full runs, Strat,Scholo and super fast DM Trib runs for gold (and gear). Expect insane amount of pvp within week or so.
Me and Kruschpak went thru alot of min max what is best and I think we both agreed on mages and shamans overall being kings in Classic (shamans bit later on with aq patch>ele )