class quests

[Orophin]

My order is ACN - MRD - GLA, or would the 2nd and 3rd need to be in any order?

If your primary class is Arcanist then you first need to decide whether you want to play Summoner (caster dps) or Scholar. (healer) That will determine which classes you need to level next. (THM or CNJ) MRD and GLA won't help with ACN but they'll help each other.