I haven't played it in years, and before the Unholy Wars version. I only played a 7 day trial. So my opinion probably won't matter much but maybe it will help give you an idea.
That said, this is my thoughts:
1) It reminded me of the Elder Scrolls in gameplay. If you have a bow, you have to aim with the bow, otherwise you miss. None of this magic arrow flying through and rolling a dice to see if you hit something. You have to aim and hit the target to do damage. It can be challenging if the target is moving. Same with spells. It was also skill based, and had no levels. You had to work up your archery skill if you wanted to be good with a bow, same with magic, etc.
2) It was full PVP. No level limits, no safe zones, etc. That said, it seemed most people that I ran into weren't big on ganking. People would mind their business and wouldn't attack you frequently, but every once in awhile I'd see a super tough looking guy come through and wipe out an area. There is also FULL LOOT PVP. Meaning, they can take everything in your inventory if they decided to do so. But usually when I was ganked, they only took the cash I had on me and left the gear. The nice part of this though is there is no radar. There was also enough fauna/trees/bushes, etc, and I was able to hide in the bushes if I seen a guy ganking someone else first. If they didn't see me, I was fine. Unlike other PVP games where players would end up on the radar and people instantly knew where you were, you could hide easily in this one.
3) There was the typical MMO quests in the noobie town but it could have just been tutorials that would tell you how to craft, get stuff, etc. Run of the mill questing like every other MMO.
4) There is natural progression in the wild. Some area might have weak goblins. The next area some poison spitting spiders that attack you from afar. I didn't notice any quest hubs in my experience, but rather just mob grinding areas that you have to go from one area to the next as you skill up. I never found a dungeon, so I'm not aware if any exist.
5) The graphics were functional, but not spectacular. That said, there is no motion tracking cameras with the animations. But rather it looks like someone made animations from hand. This can be quite a shock to people as the animations look like something from a 1990's game. But if you can handle that, the graphics weren't too bad. Obviously not at an Elder Scrolls level, but rather a game made early to mid 2000's.
I did think I would like the game when I was playing, but to me it really seemed like a game you needed friends to play to fully enjoy. It was not solo friendly at all. If you were fighting and needed a heal, you had to swap out your sword, equip a wand, cast your heal, go back to equipping the sword, etc. It was very tedious so having a friend to just heal in the background while you were fighting would have been very handy. If I had a group of friends wanting to play, I probably would have stuck with it, and subscribed. If you are playing by yourself, I suggest finding friends before purchasing the game (try to find a guild on some forums first).
I never really got past the noobie areas so I can't really comment more about the end game or guild PVP/siege warfare, etc.