I liked the idea of a DOT heavy pet commander, with some basic healing, tactician. thats why I picked arcanist to start with. they removed like 3 DOTS, so now its a blm. except 1/2 its damage AND utility is tied to the 60 sec cooldown aetherflow, with like 6 abilities being chained to that cooldown, and useless without it. so if you misclick, poof, thats it, you pretty much sit there doing nothing.
you cant heal (heals like .001% of health for 30% mp)
you can barely dps without dreadworm...but you spend 80% of dreadworm time waiting for GCD
you get one pet choice
you have to spread dots for AOE...but you cant do that more than every 60 secs

I dont think a rebuild is needed. I think even something as simple as making it so you can have aetherflow and aethertrail stacks concurrently, like before, would help alot.
jack of no trades, master of swearing-cuz-you-forgot-you-already-had-2-aethertrail-and-wasted-aetherflow-cooldown and now cant really do anything