Classes played: Bear Shaman, Ranger, Conqueror. No PvP was involved, but heaving grouping was.
Combat - The lack of auto attack is a nice idea, but there are only three default attacks: right, straight and left. As far as I could tell though, there is no difference between swinging right or left; even if my attacker swings right and I swing right, I'm just as likely to hit as I am miss. If this were based on reality, it would make more sense to have a head shot, body shot and leg shot. Once you start gaining abilities, however, you realize that the right-straight-left attacks are nothing more than DDR-esque triggers to set off combos.
The combo system, at first, seems nice. In fact, a lot of what AoC offers seems, at first, to be pretty nice. In the end though it comes down to just trying to spam as many combos as you can in some random order. Sure, getting the bleed attacks off first might seem like a good idea and if you're in a group, taunting abilities are useful to start with, but the order doesn't really change the outcome of the battle... I've never once thought "oh whew, it's a good thing I got that X combo off in time instead of Y combo, otherwise I would've died!" I'm sure someone with an excel sheet could figure out the best order for the most damage with the least amount of cooldown time, but at the early stages, none of this matters.
Load Screens - The only load screen worth complaining about is the very first one you have to sit through when you try to enter the game. That particular one takes about five minutes to complete and is extremely annoying. Every other load screen I ran across when moving between zones only took about 10 seconds to get through at the most. So why are people complaining so much about it? Probably because it takes several days to download and patch the game, so waiting those five extra minutes when trying to get in for the first time can seem like a nightmare (PS: this is a nice way of saying that people just like to QQ when they don't get their way).
Graphics - Extremely beautiful. The colors especially. The only concern I have is that the armor at the beginning is very boring. It's realistic, but it lacks any artistic touch that makes you hesitate to dump one old armor for a newer one. In fact, most of the time I couldn't wait to get out of the gear I was in, if only so that I could look at something different.
Class Imbalance - First off, if you decide to play a healer, you're going to suffer a lot. I dropped my Bear Shaman when I couldn't continue with the main storyline (which, by the way, you're FORCED to solo) because I had trouble defeating two enemies at the same level (I couldn't even kill one, respawn, and then take out the other). The Bear Shaman was slow and weak, and the only healing ability I had at the time was a HOT.
I then tried a Ranger. Rangers are just warriors who can stealth and have a few bow specials. Yawn. It was pretty boring.
Finally I went with a Conqueror. The warrior class focused on buffs, debuffs (which always seemed extremely weak), and straight up damage. I could survive groups of three if I made sure my enemies were all clustered together, since I had a massive 2-hander that did cone-like damage in front of me. The most important thing though was that I could solo the main storyline. I couldn't do that on my healer. My fiance also had trouble soloing on his Necro, even with a demon pet, and he greatly preferred grouping with my Conqueror since he wouldn't die against every group of two that came at him.
Forced Soloing - This is, without a doubt, the biggest complaint I have about this game. No game should force you to solo something. What's worse is that the solo/storyline content levels up with you, so trying to go back and deal with it when you're a bit stronger will not work. I'm not sure if completing this is required for players to get off the island, but even if it isn't, you miss out on the best quest rewards and interesting stories that change depending on which class archetype you play. Maybe, just maybe, this will be changed for release, but if not, I can honestly say this is what's keeping me away from the game. If I want to play by myself, I'll fire up Mass Effect, thanks.
Final Things - There are a lot of decisions you can make when it comes to customizing your character, both in appearance and skills. Creating characters is probably one of the most entertaining aspects of this game. I also absolutely adore how RPG-like holding conversations with characters is. Actually being able to interact with characters and say different things to them is something that MMOs have been desperately needing, and I love picking between different choices to see what types of responses I'll get.
Sadly, combat, class imbalances and, most importantly, forced soloing, really take away from the experience. Since this is a beta, it's hard to know exactly what things will be like in the official version, but unless there were some major changes done, I just don't see AoC becoming my next MMO.