Thanks for raising this, @FictionNet – it's an important discussion, and I think both sides (affiliates and casinos) have valid concerns.
The main reason so many affiliates prefer CPA is because they're doing media buying. They’re paying for traffic upfront and usually aiming to get back...
Nobody would pay for 3 page site
nobody would pay that price for 3 page site with ads income, this is super high risky - Google is like a monkey with granate this days...
try to work more on content, make subpages/blog posts + some backlinks, many publishers would love to link to such sources...