Tex,
I may be going against the grain here? If your market segmentation is going to be the higher end, I'd go with plastic bags with a valve for the whole beans. For those customers that want your beans but have no grinder, then go with the paper bags with ties. I have tried to get all my customers (churches) to get grinders, but many don't/won't and I still take our great greens, roast, and let rest and then GRIND>>>>> ugh! However, I provide what the customer wants. I'd suggest having both for the fair.
My "understanding customers" want valves and understand I roast fresh and they need time to de-gas.
My two cents worth. BTY, I have some nifty labels that can be placed on each bag for discription purposes. Variety, "Fair Trade", weight, roast level, etc. You can make your own on the computer.... Jim