Nobody likes the idea of a sorcerer using a fire emblem, since they don't have as many DoTs as wizards who use their tree better.However, I feel in PVP a fire sorcerer built would be massively OP, but specifically just for pvp. You won't have to put many points into your healing tree but you definitely need a 5/5 firel/wind emblem.
The trick is to switch to fire emblem on all of your x4 damage attacks. If a regular sorc could do 6k to someone, you could potentially do 7k with the same attack. Theoretically it could help you kill players faster. With memorize and frost diver, you could still combo and hit way harder than any other sorc, simply because of the emblem alone, so the haste advantage from it won't be missed with that skill. I think a fire/wind sorc is the best for PVP, just seems that they would the best. No need for fireball or anything, just the normal sorc strat with the fire emblem when you can.