I use auto-run to quickly roll on loot between pulls while taking my left thumb off the controller stick. It’s courteous to go ahead and roll if you can, rather than waiting for the timer to finish, but it doesn’t actually impact anyone until the end of the dungeon when someone might be waiting for you to make your roll when otherwise they could leave.

(I really wish the devs would implement an auto-roller. I would love to automatically roll Need/Greed on higher level dungeons, and Pass on lower level ones.)

As for mob packs in dungeons, I like them. They give a different kind of gameplay for tanks and healers, and they’re very fun for Reapers because we get to build lots of extra gauge from all those deaths. :3