Maybe this has been mentioned already but these decks are mostly for beginners and not many beginners would be able to properly handle PowCham. They would either end up falling too far behind or would never use Pow! properly, if at all. This is probably the same reason that Ross' deck didn't make the cut. Where as you look at NidoQueen and it couldn't be more straight forward. Evo lines are expanded for consistency, key cards are there in multiples, etc. Overall its a much easier deck to use. That, and it won 15+.