I think pokemon emerald is better than any other pokemon game because:
1. yeah sure its not in third dimension but its 2d is old school.
2. the ds pokemon games have lower creativity pokemon black 2 and pokemon white 2 is second on my opinion list.
3. it goes a little faster and smoother than other pokemon ds games xept for black & white 2.
4. swampert is one of my favorites.
5. hoenn region is pretty big.
6. only pokemon R, S, E and fifth generation have the hidden move dive.
7. you can get lots of legendaries(kyogre, groundon, rayquaza, mew, jirachi, etc.) I heard that you can get an arceus in pokemon emerald but I think that is a lie. :P
8. the running animation is smoother in the GBA games.
Game Freak's creativity is getting lower and I predict that they might remake pokemon R, S, and E for the DS, 3DS, WiiU, etc.
pokemon with weapons might be their last resort to creativity. 0_o