I feel challenges for second should be used, if all tournaments, not just the large ones, used the challenge format, kids would be used to it. We have used the challenges at our tournament in Columbus for the last couple of years with mixed feelings, the main problem we have is it is different than they are used to.

As for the extra matches created, you could eliminate the 3rd/4th place match if the kids have already wrestled on the front side of the bracket.