For me i'd go to hunter or warrior. Assasins and priest are not meant to do close quarter combat like using your physical strength to defeat enemies but using your brain and strategy of how to take them down.

I tried going through the game as the assassin, and it was literally impossible. As in, I couldn't kill a hunter / warrior duo in the third / 4th stage. I simply couldn't do enough damage to kill them before they killed me. I tried blocking, stunlocking, kiting, using different food buffs, and I even grinded an extra level and went back and bought a couple of pieces of armor for extra defense. Tried respeccing, but nothing worked... the damage simply wasn't there. Keep in mind that this is on hard.

So I rerolled hunter (I had already bought premium, so I already had 2 free talent points with assassin). Hunters are incredibly overpowered... the dart is basically a 3 second stun on multiple targets with a 6 second CD, choke is an AOE spell that deals 2.5x your int (LOL). Riposte is a guaranteed block (for 100% damage) that doesn't require you to crouch, and gives you a stun + 100% bonus dmg on ur next attack. They also have a heal with no cooldown. This is absolutely absurd compared to the assassin, who has a 120 second CD on his potion. Basically, you just stack int and you can destroy anything because the hunter has HUGE int modifiers on his spells.

I agree, if you bought Premium, the Hunter is by far the most powerful class. In addition to what Ixoziel said, Hunters also have a dash with a 1 second CD and guaranteed critical chance on the next hit, a stealth ability available at low levels and an ultimate that deals about twelve times (!) your weapon damage to your enemy, plus base damage and Strength scaling. If you equip Kabuki Mask/Mask of Insanity and the right talents, you can deal 11K crits with your basic attack at the end of a combo.

The rest of the classes are actually dependent on whether or not you bought the expansion: Priests are the most powerful pre-expansion, since you can kill anything in a few shots by spamming your main damage spell from one edge of the map and get a lot of tanky abilities late game, but fall off in the Throne of Flame, where enemies can get to you quicker and become untargetable. Assassins suck towards the end of Sinjid pre-expansion, but with enough Shadow Gems to boost their attack speed and Throne of Flame's better item sets they do pretty well. Warriors are good throughout the whole game, and really become godly after you play for premium, as you get to pick all the good damaging and tanky talents you need.

I beat normal with Assassin fairly easily (mirage was op).

I play better with the priest, although I'm still level 6 or so. Hope I can finish the game today or tomorrow. Also, I have played with the warrior class and didn't find it very useful at first. Didn't play with the assassin class as of yet, but will do so as soon as I finish the game with both priest and warrior.

It depends on how you want to play. The Assassin class is best for diving in and out of battle. From what I've seen of the Monk, it is king of ranged attack (non-premium, idk about the hunter). If you want to be able to survive even under a gauntlet, use the Warrior (if you run into a problem of the enemies running away, fully upgrade the Kunai spec).

assasin is the best

Character movement's a bit too slow for me >.<
I found it a bit frustrating. But it may change as I get used to it.. hehehe

I'm trying the assassin right now and I think it's the best because it has double strike, higher crit chance. :D
Although, it dies too easily >.

Not really if you now what to do. You could also save some money and buy some food that temporarily raises your stats (2-3 coins each), it can help a bit. Personally i've only died like 2 or 3 times and on boss lvls.