I really don't get why they don't make a pokemon MMO. I mean really, it's surely the perfect one to do. Obviously some world expanding would need to happen, 4x bigger maybe, but fundamentally the same still. Have all existing regions, gyms and tournaments available, and add a bit more sandbox to the world, player gyms etc. Have all the battle options from the latest games..as new games come out.. bosh expansion with the new regions and monsters etc..
Anyway I have to say HG/SS really are the pinnacle, they have all the charm, and fun of the original and the multilayer is great, even if it could do with a tiny bit more options.