I actually do use Boyd myself (Because to me he's more Draco than Tom Felton ever was), and I don't generally make icons as a rule, so that means finding the "right" model means little to no icons, because they're rarely iconned by more than one iconner.
And then, there's the fact that most people just aren't as discriminating as they might otherwise be. Sounds like you've got a good standard about it, but a lot of people just look for someone "pretty enough." Which isn't what finding a PB should be about.
But yeah, there's always exceptions to the rule. I've just found I like actors more, because generally you can find them in much greater variety in expression, clothes, and quantity.