Most low apm dps class and why ?

[Kacho_Nacho]

Decided to go RDM since already leveling caster class to 80 (BLM) so gearwise will be shared with RDM

Good choice! It has slightly more actions per minute than a black mage but is easier to play well.

Now, if the melee bug bites you, I'd suggest monk. I suffer from fibromyalgia, which causes pain and difficulty in concentration, and I have found monk easier the dragoon. Although, I have to say, dragoon is more enjoyable.