I dislike speedrunning dungeons on the basis that AoE is the single most boring thing to do.
As an example, compare the actions for a Dragoon performing an optimal single target rotation to the actions required of an optimal AoE rotation.

Personally, I use Dungeons as learning experiences to fine tune my rotations, So speedrun AoE spamfests are not only unhelpful, But downright sleep inducing.
I absolutely understand the desire to get through them as fast as possible though.

Unfortunately for me, I still love the old school "dungeon crawl". Long ass dungeons with large numbers of bosses, minibosses and hidden chests and pathways. That's what I've enjoyed, But the current generation of MMO's dont include them.
Would like to see alternative longer dungeons for those of us that like longer crawls.