yeah as people already stated, almost no requirement of gear even required for esseles at all! Just remember to interrupt his headshot/snipe ability. I don't know why people always assume Esseles is so hard, he's got one ability that doesn't require lightning quick reflexes to interrupt, and the rest whilst not super easy if it's your first time should be pretty easy in comparison. And then the rest of the dungeon is a cakewalk in any gear.
I guess it's just that people hear horror stories of wiping for ages by people who weren't sure what to do and it's escalated into this massively feared boss, and you end up dreading doing esseles. As soon as you do it with a group who knows what they're doing, you'll see how easy it is!
In fairness, the last boss in the encounter, Vokk, was ridiculously overtuned until the patch about a month ago that nerfed him. Now he's probably a bit too easy, but originally his lightning strike would hit people who were well outside the reticles and his saber throw hit two targets like a truck.