Your policy seems reasonable. Although I wonder if the analogy with a regular lottery might risk confusing people. When one thinks of “entering a regular lottery for charitable giving”, one might think of additional money—money that counterfactually wouldn’t have gone to charity. But that’s not true of donor lotteries—there is no additional money.
On your second point: “making requests to pool money in a way that rich donors expect to lose control” describes the EA Funds, which I don’t think are a scam. In fact, the EA funds pool money in such a way that donors are certain to lose control.
Your policy seems reasonable. Although I wonder if the analogy with a regular lottery might risk confusing people. When one thinks of “entering a regular lottery for charitable giving”, one might think of additional money—money that counterfactually wouldn’t have gone to charity. But that’s not true of donor lotteries—there is no additional money.
On your second point: “making requests to pool money in a way that rich donors expect to lose control” describes the EA Funds, which I don’t think are a scam. In fact, the EA funds pool money in such a way that donors are certain to lose control.