How to level dps alts?

[Kukajoo]

Is doing low level fates via Level Sync efficient?

if you have to sync to a fate its probably not efficient leveling wise at all. I do them more as time passers for the dungeons which are the real meat of exp that isnt POTD. On aether i've found que times arent too too terrible, 10-15 mins per que unless its super late at night, then the time stretches a bit.