Pokemon as of right now feels like one of those PC indie games where people can pay early to play the Alpha and Beta before it's final release.

Gen 1: Alpha stage with basic concept and a fuck ton of problems/glitches.

Gen 2: Alpha 1.2 with small new features and bug fixes.

Gen 3: Beta version with new mechanics(abilities) , better functionality of old mechanics(Shines' Calcs), Individual sprites for pokemon in overworld and PC, vast amount of new pokemon.

Gen 4: Beta 1.2 with more Pokemon, more abilities, more moves, Started Wifi battling and trading

Gen 5: Beta 1.3 with an expansion of new pokemon, abilities (including DW) and more moves. better wifi, Change TMs for the better, better display for weather effects, etc etc

Gen 6: Full Game release with upgraded graphics, updated mechanics of all the old versions, more pokemon with a new type for balance, bunch of side stuff people always wanted (Petting your pokemon / easier EV training w/e)


The way I see it, Gen 1 & 2 were the blueprints while gen 3-5 were the expansion packs further perfecting the game. Gen 6 is probably no where near the "perfect" pokemon game but it still a huge step up and feels like it would be a final product of a game that's been in development for years.