It usually brings in *significantly* more money if you hold a raffle instead of a silent auction for a quilt. Check to see if raffles are legal in your state; if they are, there may be some requirements regarding ticket sales. It depends on your area, but it usually works to sell tickets for $1 each, and 6 tickets for $5. A lot of people will pay $5 for raffle tickets, but not many will bid several hundred dollars for a quilt.
Falling Charms is pretty fast. There is a Youtube video for it. I would suggest making the sashing strips thinner, though (2" instead of 2.5") and/or increase the square size from 5" to 6.5".