I agree that it is unsettling to not receive a block when you have spent the time to make one to send.
I also agree that not all the new folks are the ones guilty of not sending blocks.
This doesn't happen all the time and I've been fortunate to receive a lovely block each month from the persons above me on each list.
Here is my suggestion....maybe not popular with the one responsible for the swap because of the extra work...but a suggestion for solution.
We sign up as usual and make our block for the person below us on the list.
Then we send the block along with a stamped self addressed envelope to the person coordinating the swap.
When the deadline for receiving the blocks is met, she/he then marks those off who have not sent her/him a block to forward.
Blocks are inserted in the envelopes according to the "new" list and sent out to those who have "earned their block".
We could reward the keeper of the list by sending a bonus block once in a while.
This would insure that everyone who makes a block gets a block.
It's a suggestion, you can
me if you want.