I think it will be very difficult to improve the endgame without huge changes to the game mechanics. WvW is the only place where GW2’s endgame rises above the competition. I think they should work on improving that first.
Not necessarily. Remember the first room of The Deep in GW1?
With a 12 man party and each of the 4 transporters only letting 3 players, the group had to make sure to organize in a way that (almost) every 3 man team ended up with at least one healer to defeat the first few aspects of Kanaxai. After that, the group reunited.
What people crave as endgame is forced specialization, but what GW2 was built around is to prevent the need for this kind of playstyle. Since the every player in a party can essentially do everything, it might as well be considered a single player. How do you break this holistic trinity? By physically separating players from each other and giving them unique challenges that require every team member to succeed on their own in order to progress.
In GW1, the meta for most endgame group builds evolved to a point where the team separated into highly specialized sub groups that simultaneously worked on completing quests in order to get to the reward as fast as possible. Teams didn’t have to split up to finish the content, but the risk/reward ratio was higher when taking on quests as a 3 or 2 man team compared to a full party. GW2 could design content(I think they already did that with a fractal) around separating players and forcing them to depend on each other at certain points without being able to help them out of they slack. It’s far less accessible and encourages elitism a bit more than the current system, but it’s what a certain group of players want from their end game.
Another example at player separation is the final mission of GW Factions, where the boss could teleport a player into an “out” and replace him with one of his minions. The player could make his way through the “out” past some hard hitting enemies, or wait for his team to kill the enemy replacement, which would transport him back into the arena.
You can use the basic mechanic in GW2 as well to single out one or two party members, but instead of an easy “kill the replacement or run to the portal”, you could turn one or two party members into minions of the boss, that suffer heavy health degen and are forced to attack their teammates to stay alive long enough until they can, let’s say knock down the boss to force him to release his spell on the “evil” party members.
If you want a kind of endgame that allows and requires specialization, you have to separate party members from each other. If you allow players to choose who is separated into which solo challenge, you can turn up the difficulty/specialization even more. Create a room for a dungeon that requires a player to survive as long as possible in order to allow the others access to an area that – once completed – will free you and allow you to return to your team. Naturally, players would start demanding certain professions with certain survival heavy builds to maximize their chances at completing this challenge.