It could only help sales if the size of the box for any upcoming product would fit into one of the 5 flat rate shipping boxes from the USPS. The current Base set is a few inches too big to fit in the elongated medium box. the Tomes on the other hand are fine as two can fit nicely into a small flat rate box. This would allow you, as well as retailers, to charge a reasonable price for shipping to international buyers.
Hedge