I tried last year but did not have time to do DnD's justice. The swap system makes it easy to participate in more than one swap here at the same time, and I may try that again someday.
I think one approach would be to look at wish lists from both swaps and see if there is a trend you could follow regarding what is more interesting to each group. I would also look at seeds offered, which will give you a clue about what people like. It would also help you decide where to place seeds. If you see that something you have is already being offered in one swap you can place yours in the other.
You could also use those lists to see if there is a niche that needs to be filled. And, you can tailor your offerings to reflect the number of packets you are interested in and place more seeds where you see more that you will be dibbing for during the swap period for each swap.
I'm an over-thinker. Sorry.
If it isn't too complicated I can make it so.
