The reader I like the most does both Keen and her own site. I've asked her things about how Keen works in the past and she has told me before that even though she keeps all the money on her own, Keen always has customers non stop. She said she prefers readings on her own but when she wants to make money right then and there, she'll go on Keen. So I guess it serves it's purpose in both aspects. But she's also really busy when she goes on. The mediocre readers might not have as much luck with Keen.
To the point about taking payments, I've had a (very) small business for a few years and I know that Facebook won't let you take payments as a business and if they find out, they'll cancel both people's ability to send payments (found out the hard way). Every psychic I've ever utilized independently just uses PayPal though and it seems to work just fine. There's also a thing called "click advisor" or something like that which will run a chat software that kicks out the customer when time is up (same as Keen) so it has the exact same functionality as Keen chat except it takes much less of a cut. The customers have to sign up for an account with them but it's basically the same as Keen but it's the psychic's own advertising. I know about it from an advisor using it who you all had mentioned on this platform lol.
But as far as the price increase, I don't think it will be an issue for anyone (advisor wise) as long as they don't increase the fee. I've only called one psychic who was less than $1.99 and I liked her just fine, but there weren't too many advisors hanging out in that price region anyway.