Of Holes and A-Holes

[Neo-Scholastic]

Something like that. It's a generally Aristotelian conception of Reality.

According to Aristotle, both matter and form can be perceived by senses, so they'd both be considered material.

Not exactly, for any sensible object you can inquire about it with four basic questions: 1)Of what is it made? 2)How did it come to be? 3)How is it structured? 4)How can it change? Each question has a corresponding cause: material, efficient, form, and final.

Saying, as you do, that everything is material implies that the other three causes are subordinate to material, which is not the case. Someone would be equally justified in saying that material is subordinate to form. In fact one famous physicist whose name escapes me once said, "At the bottom of it all reality seems to be structured nothingness." i.e. all form.

As it relates to the OP and holes, I say that holes exist, but only as a formal property with the potential for manifesting in reality as part of a sensible body.