It has to re-developed, thats clear. But other games showed, that it is possible if the developers do it right. And new campaigns or expansions. For me, it's the same :D.
The main reason I love GW 1 is, that it is easy to learn and easy to play. It's just relaxed. I use click to walk and the buttons 1-8- You don't need more. Because GW 2 doesent't have click to walk I dont have fun with it. (as you can read [here](https://en-forum.guildwars2.com/discussion/74260/suggestion-click-to-walk-run-like-in-guild-wars-1-why-im-not-playing-guild-wars-2)) But I love the hole gameplay and the scope the game gives me.
**@Arenanet: Why don't you do not a proof of concept? Re-Develop the Prophecies-Tutorial and look how the gamers react to it?**