I was a major GW1 Mesmer player. It was my first PVE character and I played a lot of it in PVP. I made a lot of Mes builds. So my purpose in this beta was to give the Mesmer class a hard look. I loved the beta and I'm hooked, but these are my Mes impressions.
Good stuff:
Sword and melee worked better and felt more enjoyable than I was expecting, at least against one to three mobs. Of course, like every other melee, they suffered once you plowed into a large DE or a WvWvW siege.
There are some more Mesmery skills such as Mirrored Feedback and Mimic, though Mimic felt a little bit clunky in working it.
I also enjoyed the Staff a lot more than I was expecting. I think they have improved the damage of WoChaos from initial playtests. In large groups, the condition and boon aoe is very useful in a support role, even though the boons and conditions are random. You plop Chaos Storm on top of a large group and good things tend to happen. It was also quite easy to pop up illusions with the staff compared to say the Greatsword.
Meh Things:
Greatsword's Mindstab felt like the best skill in the GS skillset. I saw some big damage numbers with it and it applies a good stack of vulnerability. It seems to work like how Shatter Dillusions worked, in that the debuff hits before the damage thus increasing the effective spike. There is still plenty of spatial surge spam to be had, but its not in a 1-button spammy way like it looked in the press betas. On the other hand, the phantom summoning from Phantasm Beserker is really ineffective. Too much inactive time from the phantasm and it takes too long to even show up in the playing field.
I wasn't finding much use out of the Focus skills.I also noticed that Focus had a damage stat tied to it though I had no direct attack skills with the focus weapon. Not sure how that is working right now.
Problematic things:
The entire illusion and shatter class mechanic is not really working. Single mobs die too quickly to even bother with using the illusion summonings on them. Path finding AI creates a major delivery issue problem. When you are thinking "I need to daze this foe", you end up getting frustrated with the delay from your clones running at the target and the continued delay if the target runs away. If your illusions die along the way then you wasted multiple actions and CDs to accomplish less or nothing. If your target runs out of range, then your illusions just stand there, do nothing and cannot be shattered.If your target dies soon after a summoning then you blew a CD and got zero out of it. This is especially annoying for phantasms.
Shatters are also useless vs doors and environmental objects. This just shouldn't work this way. A huge part of a class shouldn't be rendered useless versus a major part of WvWvW.
The whole "Multiple inputs for the same effect that suffers from unreliability" is kind of the whole problem with illusions and shatters. That along with the great difference between use of clones (shatter bomb and ineffective distraction*) and phantasms which actually apply some useful thing at times. The two types of illusions are in conflict with each other because they both get shattered at the same time.
*Stealth and clones work better as a distraction, but again that's a lot of button pressing for one trick.
Mantras and Mantra traits weren't all working correctly. I expect this to be fixed, but it kind of threw out any mantra-based build from being used in PvP.
For some reason they took the confusion off of the scepter's Ether Bolt. They added some more damage to the Ether Bolt skill, but the removal of Confusion application kind of screwed over relying on confusion as an effective damage or deterrent.
Overall feelings:
I enjoyed playing the Mesmer, but I've come to wonder if I wasn't just enjoying the game overall and the Mesmer class didn't get in the way of that. I can say that the Mesmer didn't feel like a Mesmer and if they took bows and every huntery or rangery thing away from a Ranger then there'd be a great outrage. I think the reason there isn't as much outcry over this is because the Mesmer class doesn't exist outside of GW and so people are less familiar with what defines the class. Plus, clones and spell effects of a Mesmer are enough kitsch fun to distract people from inherit design issues.
Saying "It's a new game, you can't expect the same." doesn't really apply here. It being a new game hasn't taken the flavor from any other class. The newness isn't an excuse. If you put a class from the last game into the next game then you are taking on the responsibility of making that class work in the design of the new game. The Mesmer style is not working currently within the design.
They need to fix phantasms and realize that clones and phantasms aren't close enough in purpose to tie them to the same mechanic. They probably need to look at the class mechanic, see its not working well enough and go in a new direction. I know in the GI video with one of the designers, he dropped that they are revamping the Mesmer. I hope we see some changes from that revamp within the next couple of betas. The Necro has changed its core mechanic, so it's nothing new for Anet to do.