I know a lot of people have been asking about having all 4 regions playable, and also a lot of people have pointed out that the levels would have to keep getting higher
Personally, I would like HGSS to be harder than the originals. Have more story (especially in Kanto) and it would be awesome if they added the Orange Islands properly this time. By this I meen adding the four gyms of the orange islands and then the OI championship - kinda like the Battle Towers in the newer games, but where gym leaders and past trainers are also present with massively improved teams.
Finally, I believe a game with all 4 current regions will come in the next gen. With the 5th gen adding a new 8 gyms but no pokemon league. Once these 4 gyms are done you have to go to the other regions and beat their gyms, with the gyms of the other regions being 40-75. Following this would be all 5 pokemon leagues, and then ongoing championships - with all 500pokemon available.
G_L_P