Step 1 : remove Mesmer from the game. Sorry guys, you are annoying and make a mess on the battlefield :p
Step 2 : some fights end far too quickly : remove all the high damage low defense items
Step 3 : some fights never end : remove all the high defense/healing items.
Heck, remove all the amulets. No stats for everyone except traits! And remove all healing from the game except a constant slow HP regeneration. Remove Protection boon and remove the quick HP healing out of combat. Probably should also nerf dodges a lot, like, remove Vigor or make a dodge use all endurance at once. Or both.
Maybe then the fights will be more interesting
Edit: I forgot that part.
And do that not on the default game but in a special Tournament. The “test” tournament where you beta test gameplay changes like a real test server but even better.