The plan for adding spell making has been in for a while but I haven't seen any plans for new weapon skill tree's, though I haven't seen any update as too the addition of new weapon sets and skill trees
It's been kinda sad to me as the elder scrolls games in general have been simplifying their weapon list since TES3 which had everything from current 2 handed and one handed to the inclusion of combat staves and spears where as with TES4 to ESO there has only been the inclusion of the core trees and baring it down to they all use the same animations eg. stabbing with an axe during puncture which makes NO sense.
It would be very interesting to see something like a polearms skill tree for dedicated melee stamina control. Large sweeping attacks with a scythe or glaive
or the inclusion of an alternate one handed line for spear allowing for attacks while blocking that might do less damage or use more stamina.