Quoted By:
I wish Emerald fixed more of Ruby and Sapphire's issues. As it is, it adds a bunch of new things in the post-game, that's fine and all, but I think a lot of that stuff should have been in Ruby and Sapphire to begin with, those games were really lacking for content. Even the things that Emerald added had an asterisk. Steven is a Red-like final boss, but he's worse in every way, lacks any of the intrigue, and can only be battled once. Trainer Hill is added but require e-Reader cards to fully enjoy, which weren't released outside Japan and have been randomized since FRLG. Gym Leader rematches with multiple upgrading teams are now possible but have so much inane bullshit behind them. You can get a Johto starter but it requires COMPLETING the Hoenn Pokédex, that's going to take three people with Emerald all coordinating from the start. There's the Union Room with up to 16 people but you can't even use it unless you have a Wireless Adapter (this blocks the charger on an SP, and the Game Boy Micro needs its own special Wireless Adapter). Altering Cave has been added, but it goes completely unused and it's pointless since you can already catch those Pokémon elsewhere in the game. Navel Rock and Birth Island events were added, but they're just copied and pasted from FRLG. Faraway Island with Mew is totally new, but they never released the event outside Japan.
On the opposite end, I don't think Platinum really does that much for Diamond and Pearl. It has more, but they were already filled with content to begin with. Even the number of Pokémon added is pretty small. Articuno, Zapdos, Moltres are roamers now, Regirock, Regice, and Registeel are available with an event Regigigas, and Tropius, Tangela, and Tangrowth are finally in normally when they weren't before for whatever reason, especially with Tangrowth being a Gen IV Pokémon and Tropius being the ultimate HM slave.