About Pokemon LeafGreen@THUNDERRSLASH - That's just due to region differences. The first Pokémon games to be released in Japan were Pokémon Red and Green versions. Later, Japan received the blue version, with updated sprites and fixed glitches.
When localizing the games to English, the games were released as Pokémon Red and Blue, using the sprites and fixes from the Japanese Blue and the available Pokémon from Red and Green. Green never saw a localized release. I assume this was down to marketing - No offense to Venusaur, but Charizard and Blastoise probably looked cooler than Venusaur to a 90's kid.
By the time remakes were due, the Pokémon fad was long over, and most of it's fans were either young children or diehard fans. Pokémon Red and Green were remade into Pokémon FireRed and LeafGreen in Japan, and because it wasn't necessary, the didn't bother to replace Leafgreen with Blue for the worldwide release - It wasn't necessary and would've taken more work to make new promotional artwork featuring Blastoise rather than Venusaur, when the Venusaur promotional material was already in existence.
So the remakes are based on the very first Pokémon games, Red and Green, and the lack of a Blue remake can simply be attributed to the fact that is was unnecessary work.
*I love FR/LG, I voted for it just to make this piece of Pokéhistory clear to you and everybody;)*
Also, I notice you've commented on WAY too many games on this list. Are you a Pokémon hater, a troll or a Genwunner? You seem to have voted for everything except Red, and hated Soulsilver because it was, ahem, "totally changed."... Seriously?
Thanks for your input - THUNDERRSLASH