The ability to design your main character. It would be hard for me to see this in the main series though (even though it would be awesome), so at least if they ever made something similar to Colleseum (sp?) or xD. And if they were ever to do another one of those console adventures they should expand it much more.
Bring back the contests from the 3rd generation and pokewalking (irl and on the game when they follow you). Also, secret bases were awesome. And no more of the stupid contests/fashion shows/musical things. Blergh.
This'll never happen because Nintendo is a cash cow but they should have every pokemon of a generation in both of the generation's games. Like, not taking Growlithe out of this one and Vulpix out of that one. And no out-of-game events to get rare pokemon. Some people don't have wifi or the ability to tread to Gamestop or wherever whenever to download a rare pokemon.
Have sidepaths for your character. Instead of going the direct hero route all the way they could have some side-routes too that your character can accomplish that are different from the main hero path. Like, recording data on all the pokemon can give you the title professor, helping out the bad guys in a sidestory could give you the title of 'bad guy', and so on. Participating in side events in the story (which would give it a lot more depth) and earning titles for it could be pretty addictive.
I think it would be awesome to see a big console version of Pokemon (Like Colosseum and XD, but bigger, that has those side paths and is just a big giant games you can do whatever. And you can go off to be a master, professor, gym leader, ranger, bad guy, whatever. And choose what kind of character or trainer class you want to be.
And it's overused, but I'd love to see all the regions in one game too.
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