I'm of the impression that Bard is a good subclass for PvE spec, Slinger for PvP, and Sorc for all-rounder/both. Bards are great for extra survivability when grinding/mobbing and dungeons. Gunslingers have an extra slow, traps are cool especially for that damage reduction buff, extra movespeed means better kiting, and the speed buff is coolbeans if you wanna focus more on crit. Sorc can both heal and offer damage/cc, so it kinda takes the cake, but its also the most boring/expected combo imo so I personally dislike it.
Keep in mind that this doesn't mean a bard subclass sucks at PvE or Slinger sub sucks at PvE. Obviously all of them have merit, its what you like better that matters.
On a different topic, I wonder why people don't consider Grenadier as a Wizard subclass. I'd have thought they'd work just as well as the standard choices.
The dmg reduction buff of the traps doesn,t work with sub guns, they still have heavy dot dmg and nice debuff (inmobilize and healing reduction)
For the moment I consider sorc and guns as the better options, with a good bard that concentrate in heal and not in trying to be a hybrid dps (like some bards I meet in the arena...) itrs pretty hard to die right now, maybe in lvls 60+ the sub bards will start to shine against the insane dmg of the bosses.
I was curious about cannon too, it was one of my options of subclass, IMO cannon its not very popular choice cause his better skills its the stun and the ice aoe, and the wiz alredy have acces to 2 stuns and 1 ice aoe, the turrent looks cool anyway, not sure if its strong or weak