Recently my gaming group ran into an underground forest that was isolated from the world for more than 10k years.
The Arcanist fits the bill for me to portray how magic was before evolution caused the split between sorcerers and wizards.
It gives the feel that the Arcanist might have been a predecessor of the sorcerer and the wizard.
With the proposed changes, the updated Arcanist could be a sort of Higher Order of spellcaster. (Pug analogy is perfect since he studied both sides of magic).