In 2.0 I leveled my PLD through the MSQ so that was easy. Then I leveled my WAR by spamming dungeons.

Now with my fresh start, I leveled my BLM through the MSQ (1-52) and SCH through the MSQ (52-60). Then I do the daily leveling roulette on either my WHM or GLA depending on what I felt like. The leveling roulette basically gives me one level each run until about Lv 37 (except when you get the story primal fights). No burnout and easy leveling. I do run into problems with outdated gear this way, though, because getting Sastasha at level 33 isn't going to give me that sweet Battlemage gear. In the end I ran dungeons unsyncced on my Lv 60 BLM to collect tanking and healing gear. It's a quick 10-15 minutes run through Brayflox for example.

Also don't forget the XP bonus ring.