Spoilers about CoE boss skills ahead.
I’ve been reading the forums lately and read a lot about the current issues with the dungeons as well as the argument of GW2 needing a holy trinity vs remaining as is. I feel like the issue might not lie with a lack of a trinity system, but instead having boss fights that don’t seem to be designed around GW2’s combat and grouping system.
I think this is best illustrated by Kuda in CoE, but more specifically his golems that he summons with the persistent AoE poison aura that is extremely hazardous to anyone that wants to melee. If the philosophy of “bring the player, not the class” is to be followed, something like this can’t really exist without a really tanky melee player or some dedicated healing. You COULD weave in and out of melee, but doing so would be much more dangerous than just staying away from the boss. The obvious solution is to fight at ranged, but what if you want to play melee? Many people roll warriors, guardians and thieves because they want to play at melee. Why should they be denied their play style choices for a certain boss? A player should be able to play how they want, and the dungeons and bosses should still be accessible to them if they can play well. Glass cannon specs should be perfectly viable, assuming the player can properly dodge and avoid damage.
A lot of the mechanics for this are in place already, such as projectiles that are not homing, so can be sidestepped instead of having to waste a dodge. Stuff like this is great when it is properly telegraphed so the player can react accordingly. What if the golems would create a targeting reticule over the player that they are about to shoot at? This way the player would be able to easily determine where the boss is attacking even through the mass amount of particle effects that are common in group fights. The small red circle on the ground is constantly getting lost, especially in melee range. There needs to be better visual communication between the enemies and the players, so they know when they are being targeted and can act accordingly.
A great example of a boss that seems to be designed largely around the GW2 style of combat is the giant colossus boss found in Orr. He is large and easy to see, even during a huge zurg of players. His attacks, mainly the stomp, is telegraphed extremely well, so that good players can dodge and avoid his damage. He also makes a loud and consistent noise before doing so. This is a another great way for a boss to telegraph his attacks through the visual noise. Now, not all bosses need to be quite this slow and lumbering, but its just an example of a boss that I feel was done right.
Uh…so I guess I ranted on for a while. Forgive me if I jumped around from topic to topic too much.
TLDR: It might not be the combat design that is bad, but the bosses and dungeons. Also, more visual clarity is needed for players to feel like they can respond correctly.