I agree - In this type of group swap (where you are requesting what you want from others) we should expect to give up all our seeds offerings, whether or not we find an equal number to request in return.
One Idea -would be to have a 'starting limit' for requests - the opening day of the swap everyone can select a limit of say three seeds that they really want the most. This way, it will give everyone a better chance of getting those wish seeds that might be limited to only a few packs available. This could be carried over to the next day or more.
The less restrictive, I think, the better. If it gets too complicated with rules and regulations, many will probably be turned off to joining.
I think we should just let this beta swap take its course. Then we can review and address any problems that arise after the swap is over. It will probably be the exception, not the rule of people who would take advantage of this feature. Problem children can be dealt with!