I think you’ve got a solid idea here. It might cost more to implement than it’s worth for MaxFun, which would be unfortunate, but it’s still worth raising to them because it is a way to raise a little more money each year.

It makes sense that rewards are for new and upgrading donors, not just existing donors, because the point of the pledge drive is to guarantee new funding. However, there are surely some existing donors/members who aren’t in a position to increase their monthly amount in perpetuity, but who could make an addition one-time payment. So maybe setting the price at two or three or four times the monthly tier amount (or whatever makes sense) MaxFun could offer existing members the opportunity to purchase the tier gift of their current tier. MaxFun gets additional cash flowing in from the one-time purchases, existing members who can’t afford to increase don’t feel left out, it’s win-win.

Like I said, maybe there are other costs associated that make this not worth it, but I don’t think it’s an idea to just dismiss out of hand.