Giving him the ability to take control of technology and fight people while only being able to be defeated by telepaths (which we currently have none of) seems slightly unbalanced to me.

Not trying to be dickish, but if your character is incorporeal, it should cut both ways. Being a technopath would be a very powerful ability (especially given the technologically oriented groups such as the Hands of Science, NEST, etc) without counting the fact that destroying the machine he's inhabating wouldn't destroy him.

Lot of potential for chaos there. He could inhabit a cop's gun and shoot someone innocent, set off bombs, etc, etc.