Been playing a couple of different chars, but still favor Feral:
Arms Warrior: Very strong, but eventually I got bored of facing “mirror” matches in arena where nobody gets a kill until the healer is OOM.
Frost DK: Always liked the more direct damage of the frost spells, and with the Frostworm’s Fury + Abomination Limb introduction actually has some viability in arena. However, complete garbage in 2s (which I like to play the most) because of lack of MS and possibility to maintain pressure. Self healing has been terrible as well.
Survival Hunter: Feels very smooth and mobile. I would’ve probably played this more if it wasn’t for the absolute need of always having someone skilled healing you (lack of people on my friends list who play healer, leads to me often being the healing hybrid myself).
Enhancement Shaman: Played this a lot back in the days, but I’ve grown tired of totems, and having self-healing as your main defense is very stressful as your health just bounces up and down the whole game.
DH: Does damage that is beyond stupid. Should be in for a nerf in my mind.
There is no class or spec that feels this good to cleave with (as long as you have stacked a lot of haste). The charging, gliding and AoE is addictive and you become annoyed at playing other classes that move in slow-motion and need 30s to kill 2 mobs.
However, the lack of utility can sometimes be frustrating, as there isn’t too much that you can do to prevent the Warrior + Ret from going APE on your teammate. In the meantime you’re just sitting there in a shammy / druid root waiting to be allowed to fight.
I only played Druid seriously so far and I have been trying to check other classes similar to Druid especially for PvP so having mobility and hybrid playstyle… I tried WW monk but their healing is really bad. I also tried Paladin but it felt very simple somehow and bad mobility and now trying Shaman which is the closest I found to Druid maybe less mobility but quite flexible and you can do many nice stuff with totems…
I also have the idea of playing Resto Druid with Feral affinity as a replacement to Feral… who knows might work.