In my opinion. Having a monk class in Elsweyr chapter would have been far fitting than a necromancer class. There are many monasteries around and there is even a main character ( forgot his name ) in the Elsweyr main storyline who is literally a monk. But currently if they are going to add monk class/unarmed skill line. I see Skyrim as the most fitting chapter since it's pretty easy to imagine a Nord going to fight with his bare hands.
No reason a monk can't use hand to hand type weapons or armor. Why not? As an example, monks in Diablo use said weapons and all types of armor
The problem with a Monk class is implementing hand-to-hand combat
How would that work regarding completing sets?
Perhaps the Psijiic skill line is ZOS version of a Monk skill line?