About the level 50 dungeons, that's something that'll happen as you reach level cap content (50, 60, 70, 80.) It's because the patch sat there for a couple years having item level go up without a corresponding equip level. If you would LIKE to make them a challenge though, see about using the party finder to recruit willing folks instead of the duty finder, and set the "minimum ilvl" option in the duty finder (make sure to mention in the party description that you're doing this.) This will set everyone to the intended power for the duty.