I went in with 0 expectations and sunk 20 hours in the Alpha. I didn't want to burn myself out, but I also have no idea when the game is actually launching, so I took the Gunlance class to level 40. I think the game is fantastic, and am excited about the launch.
The dungeons were interesting, though there are far too many mini cutscenes, where your characters all slowly climb a ladder or walk across a skinny beam. The story is decent, but I found myself spam clicking through it after level 20 or so just to get back into the action. Being able to respec your talents for free was very nice, allowing me to try out different abilities with different modifiers as I progressed.
For people who are saying the game is too easy, it is because they give you weapon boxes that give you a very high item level weapon that you won't replace anytime soon. This is made obvious because completing the first dungeon on hard mode drops lower item-level weapons than the one you get out of the gate at level 10. I think this is a good thing because otherwise, the level progression would be very slow/spongy enemies as a result. If you want an authentic experience or whatever, don't use the boxes.
PvP side: I met with a group of players dueling consistently through alpha. At the time, I was a level 30 Gunlance and dueled an Artillerist level 28. Most of the players participating were level 15, with the rules "No healing potions, no ultimates" -Your Z and/or V abilities you generate over time-) Perhaps it's my lack of knowledge of the game but ranged classes have several abilities that stagger lock you. Artillerist has a flame thrower, and if you are caught anywhere in the massive cone, you can't do anything. You just flinch and take the damage, and there are no diminishing returns that I saw. As a Warlord, my dodge ability is a unique back hop that I absolutely hated, giving me a small dodge that rarely took me out of danger. There are some abilities that give super armor, but for now, I'll leave it as "I'm new to the game, and ranged classes kick my ass for the time being".
Addressing Pay 2 Win concerns: I don't feel it's a pay 2 win model traditionally, but I could see upcoming top guilds recruiting only players who have the platinum founders pack, rushing to 50, and spending the premium currency to load out their characters and rolling the map. That's pure speculation, as I understand you can pay to upgrade your gear or do it in-game over time. This could be pretty frustrating, but I don't have any knowledge of what guild wars actually do for you, and it's not my priority. There are several streamers who state that they play in other countries 100% free to play, and sell their stuff to people paying real money, perpetually allowing them all the bonuses without spending a dime. This is a good thing IMO.
Classes. Class balance seems strange. There are 5 or so classes that won't be released at launch that are available in other countries. We have access to 14, and some of the powerhouse classes aren't available (Scouter/Demolisher/Lance Master/Arcanist seem to be the most desired based on general chat). It feels like they are gating them so that players dump their time in a first character, and then pay to gear up the new classes when they release. I'm not a fan of games having content ready and slowly introducing them for a cash grab, but 14 classes are still plenty to find something you like. Gender lock really isn't' a major issue for me, outside of not wanting to have my character look like a waifu.
So to wrap it up, as someone who went in with 0 expectations, and 0 knowledge of the game, I really enjoyed it. I think the market is in serious need of a new MMO format, and this is a game I will gamble on.