Everyone who has an Arcanist (not everyone, really ) knew: HIS E SUCKS!
The main reason it's a Channeled spell, if you can't channel it then it's useless.
So I have some suggestions here:
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And what about his R if you go "Drain" Arcanist early? His Improved R is useless!
Arcanist nearly has no contribution to the team (except the dps, ofc.) beside his Improved T (did anyone take it?) and his Empowered T (not really good because it's only make R deal extra damage to BOSSES).
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That's all, I will appreciate any comments.
*EDITED: Changed some part of the suggestion