GW1 is weird in that, theoretically and in design, it's pretty close to the most ideal MMO ever designed for me. Only The Secret World comes close. GW1 verges on near perfection.
In practice, Arena.net never had the wherewithal to tighten their own games. The flaws of GW1 are almost entirely like... UI, communication, combat feedback, et cetera.
Anet have displayed zero capacity in any of their five games in QA and secondary systems design. Even the "problems" of Guild Wars 2 are like... town clothes suck, UI is poor, feedback of combat information is obtuse, etc.
Firing a rifle, playing a DE, world presentation, etc in GW2? Brilliant. A++.
Changing town clothes or searching the auction house? Oh good lord.
You'll run into odd chunkiness in places like the character screen and hero interface in GW1. You will often be left wondering how Anet managed one of the most complex skill and builds systems in all of gaming but could not figure out how to like have whispers immediate or pets manageable.
It's like the exact opposite of Blizzard. Where Blizz nail all the secondary systems perfectly and their games play with a kind of elegance matched only by Nintendo and Valve. But have about as much complexity as the aforementioned games made for literal children.