I may possibly be leaving negative feedback for the non payer, but it is POSITIVE for future sellers who have the same problem!

Sounds like a "plan" except for one extremely important thing that you've overlooked:

If the buyer reports you, then you INSTANTLY get a Policy Violation against your account. A couple of those, and your selling account will be restricted.

... oh, and eBay removes your Feedback comment too. So that makes 2 things you've overlooked.