My personal opinion is to send to ALL, but I can see where some people simply could not afford to do that. (youngsters, people across the ocean, heck even I couldn't afford it last year.)

So here is another suggestion.

Divide all the names into even groups of 15 of less (depedning on how many sign up). Then each person can decide how many group lists they can afford to send to. This hopefully would prevent just picking out your favorite people off the master list (which is what would happen with choice #2)

It would be a bit of work for the organizer because the groups should be split fairly. dog people, cat people, pet people, young people, new users, well known people......should be represented in each list so there is a variety of people to send to. (again, preventing sending only to your friends)

Just my 2 cents.