^
MC: Sneasel/Weavile --> Corphish/Crawdaunt
I think you meant PF Sneasel and Weavile, right?
Anyway, I agree with you, sure, that could have been done, but for example:
DE: 1 Chansey/Chatot --> Lickitung/Lickilicky
The Chansey you're referring I believe is the one from the strength deck and chatot from the Tornadus/Thundurus gift set. How would it make sense in japan for them to release Lickitung instead of Chansey and then, a lonely Lickilicky in the gift set instead of Chatot?
Or like, switching the Mew Promo and one of the Espeon for Natu and Xatu wouldn't make much sense because of the time gap between their releases...
Also, I don't really count the cards from the National Beginning set, they only feature Ken Sugimori artwork (with the exception of the Grass/Fire/Water pokémon) and and some of those had already been used before (like Taillow)...
The list you made is only possible in the english release of those cards, it would be more complicated to do that in the japanese releases... What they should have done was plan the sets and the decks better to acomodate the highest number of pokémon possible... Like not being lazy in the National Beginning set, and use original artwork. And then, putting some of those pokémon in it instead of repeting pokémon...
Another example would be instead of making another Ralts and Kirlia to go with Gallade in Plasma Gale, they should have just put Gallade in PDHB; or since you're counting Shiny Collection, they would have to save Gallade until Megalo Cannon since Shiny Collection was released after SpiralForce/ThunderKnuckle... But Shiny Collection is a promo set and has a lot of reprints, so I don't count that set either... If they had made all-new cards, it would be a different story...