This submission is mostly done for getting info from the community about the idea (as a product), getting suggestions and recommendations. Because lack of time I wasn''t able to implement it on the level to be competitive with other contestants. So if you have any experience, thoughts or maybe Solidity example related referral bounties - fill free to share

Nice submission, I believe, such solutions will work later. The implementation is rather poor.

Why referral address is stored in message? It makes more sense to store it in contract data. You have to think about incentives to recruit someone. If there are no guarantees that cut will be collected, then there is no reason to recruit.

Another thing to remember are transaction fees that will eat referral cut. I think a better approach would be to implement standard wallet, but also reserve a small fee with each transaction that can only be withdrawn by referrer address or key.

The wallet ignores existence of processing and storage fees, so it can run out of funds.