How do I introduce a Chris-Kringle for my family?

My Aunty, two cousins, partners and children each all buy presents for everyone, but I feel it is getting too expensive and we can't keep it up. All up there is 14 people to buy for. Also I am the most distant family relative (I am cousin or second cousin where-as others are brother/sister, daughter, granddaughter etc), so this makes it hard for me because I also have to buy for my brother, partner, son etc as well. My Aunty has also said that it is getting too much (I am pregnant with another child so now there will be 15) and suggested to me on the phone that we should perhaps start a Chris-Kringle. I agree with her and think the others will be OK with it (one of the families and I have already arranged that we do not buy the adults presents and just the kids, but she still has 3 children). Anyway I did not want to put a dampener on christmas so didn't bring it up while we were all together, but really want to do it for next year. How (and when) do I bring this up with the other families (or should I?), and does anyone have a successful family Chris- Kringle including kids?