correct me , if I'm wrong, if borrower(partner) take loan from you and will make zero profit within month, you will get also 0+50%=0 ? from which it follows the question, how you will control your partner(he can grant private loan, publicly invisible).
P.S.
I personally have nothing against your service, if you agree hold collateral by trust escrow, but I do not think that here will be in demand.
time will tell
If the partner doesnt make profit I also dont make profit, but if he is not making money for long time then we end the partnership and swap back the money.
but did you imagined this forum has 200 lenders active and fighting for the comission to be able to roi as well to cover the montly fee?
That is good for borrowers because if drives interest rates down.