I'm not the OP, but I'll give you my reasons for why GW2 didn't work for me.
1. Gameplay was too dissimilar to GW1. I felt like I had been taken in a bait and switch.
2. Poor/no character customization. Every character was exactly like every other character of their class and weapon. MMO replayability requires diverse gameplay options, and social games require character uniqueness. GW had little of the first and none of the second.
3. Bad and inflexible control layout. This was my breaking point. What abilities I had were defined by the weapon I used, and were locked in place. In every game I like my fast attack to be on 1, my heal to be on 4, etc. In GW2 the ability keys were chosen for me and were not rebindable. This made play difficult unless you specialized in one character using a single weapon...and I don't play that way.
4. Bad storyline. A minor point for me, but the character story was not good. Some races were better than others. It wasn't good in GW1 either, so I'd overlook this, but it was a flaw.
5. Grind. Too much grind. You could avoid some grind by paying real money to buy better equipment, and I know that's a business strategy for MMOs now, but casual players like me are the least likely to engage in microtransactions *and* we hate long grinds. Put outrageous grinds in your game thinking you can mitigate it with an auction house, and you'll lose the casual playerbase.