Again it breaks down to personal preference. I didn’t have an issue doing them at 120 on the toons I did them on. I felt like they took you out of the way when I just wanted to finish the zones. Too each his own. I liked it because I would finish the quest then be right there at the hubs for the quest on the new continent after I’ve finished all the quest on the first continent.
It's not an enchantment, but you should buy or craft an iLVL 100+ belt, gloves, or boots with a gem socket for use with the new 5% bonus experience gem: Insightful Rubellite. I used a vendor-bought belt from the legacy valor vendor in Orgrimmar, since it was convenient and met the minimum ilvl bonus. Keep these in your bags until you can equip them, which should be just in time for treasure collections in WoD content. I didn't ever replace the belt until I dinged 110, since I didn't feel the stats from later upgraded belt drops made enough of a difference to outweigh the 5% bonus. This is explained below, in the WoD treasure section.