Nah ... sorry man ... I make plenty of money ... I'm a pro at my job ... but I don't like screwing people ... jeez, you think someone would add the girls and think it was as good as yours? generally even when my clients have the PSD's ... they will still come to me to edit ;) I'm good enough
Sorry, but your business model simply falls short if you're good enough ... designers are hired for skill generally ... well, I like to think so ... my clients don't usually fuck around changing shit ... Unless it's tiny ... and I don't do tiny work
$10 edits mean fuck all to me and I'd not waste my time on it :P Small changes are usually something I'll do for free as a service of support to my clients.
I see where you're going ... I just think you're looking at it the wrong way.
Btw ... even my mainstream clients get, and will continue to get fully layered and editable PSD files. I'm not gonna screw them over.