Anything collectible would suffice for me, though the Pokedex does have a role. I mean, what am I doing collecting little critters if I don't even know what are those?
I like the element rock paper scissors, too.
Also, Pokemon TCG is the first TCG I properly play with other people.
Speaking of Unowns, I would like them to evolve to each singular mono-types while their shape become the Kanji for their responding evolutions (for example, "Mizu" Kanji-shaped Unown as its Water-type evolution, etc).