I'd suggest you change the "slots" to around 0.025 for Full member , 0.075 for each additional 50 posts.
I believe that the payment for the first 50 slots is because :-
It gives assurance of an active user with sufficient new posts
It applies the signature to all previous posts
You are already massively overpaying and 0.075 BTC for each 50 additional posts will put you at around 0.0015 BTC per post , which is still at the top of signature campaigns.
You could probably cap this at 10-20 of these additional slots , and maybe making a cap per user too.
Currently , this is overcutting the next competitors by almost 100% (and even though that is awesome
) , it seems unsustainable in the long run.
I will take your word for it
Don't take that as an endorsement or assurance.
An irrational owner may still scam. I was just asserting that no rational person would scam.
A significant amount of scammers don't think rationally.
The second reason why an escrow is not really needed from their point of view is that they don't really need to start their signature campaign big , as it may prove to be unsustainable.
A smaller number of members will actually benefit them to test it out and they can increase over a month or so, after their first batch of payments.
Even without an escrow their campaign is really attractive.
