Hmm some tough choices. initially i liked them all but getting many more hours of play time with each has changed my tune.
My ranking for personal enjoyment is
1. Elementalist
2. Reaver
3. Assassin
4. Keeper
5. Katari
6. Alchemist
Warrior
Katari - I find this class a lot of fun. mighty blow is great for shutting down large groups and pommel strike hits shockingly hard. Once its armor gets patched I will work it back into my rotation
Reaver - This class is just fun to mess **** up with. rampage and the 5/5 boss just melts. Easily my number 2 class but the rampage bug not healing is really pissing me off. My struggle with this class is what to take for a 4th ability. The more I deal with the demon commander the more I am thinking combat roll. However, giving up the aoe fear is tough to do. it would be nice just to pop rampage, maul the demon commander, roll from his fear, maul him some more.
Templar/Legionnaire - I want to like tanks in this game but tanking in this game is so not fun for me. I loved to tank in world of warcraft but in this game so many people just zerg rush everything and do well that I feel no need to bring one.
Rogue
Assassin - Again like the reaver, it messes **** up. Chain spamming deathblows when aoe brings everyone to half hp is soooooooo satisfying. my number 3 class.
Alchemist - Poison feels like something is missing to really make it work. I do enjoy this class with the constant stealth action with poisons but with so much aoe flying around from a lot of classes it feels weak as hell. It's a shame as I find this more fun to play then the assassin but unless I am copying the assassin, it typically isn't as powerful.
Mage
- Elementalist - Hands down my favorite class. I use upgraded immolate/stone fist/fire wall, and meteor storm. Fire wall is extremely underrated and I use the hell out of it with this class. There are classes who get bonuses for panicked enemies and its cc with a nasty dot. It doesn't need the upgrade, but I have 4 left over points at the end so eh what the hell. Upgraded stonefist is amazing with the knockdown and the 600-1500 aoe damage it does. The class just feels really god dam powerful. It is extremely fun to play
- Keeper - Veil strike, chain lightning, static cage, and barrier give this class a ton of cc that synergizes really well with a lot of classes. This is the class I play when I just want to kick back and chill. It's extremely easy to do a very good job with support. Not to mention static cage can melt bosses with faster attacking classes. SC is way too under used imo.
The way I am playing is I play my elementalist to 20 then promote while working on 2500 fire kills. Then I go to the archer for bow kills and get them to 20 and promote. Then I do reaver to 20 for great axes and promote. Then I restart with the elementalist and repeat the cycle. It gives me a good mix of promote stats and mixes up the play styles to keep the game from getting boring.
Once fire damage is 2500 i will switch back to the keeper and work on lightning while using a frost staff. Also when archer gets to 2500 bow kills then I will swap the archer from the rotation for the alc/ass