Because 5 was a new game. Sure, the Pokemon were essentially recycles, but at least they didn't just add a bunch of shitty evolutions and call it a new generation. There is ton to love about it.
Well i guess i prefer that over garbage, shitty mecha pokemon uninspired and horrible as they could be (the color palettes with some of them are incredibly horrid, don't know what happened, and those legendaries? wow). And besides from that fact, generation 4 added many good mechanics to the game, and improved everything from the past ones.(i.e the Pokeathlon in HG or digging in D/P/Pt,). I don't know, i guess the pokemon design is the crucial deciding factor for me.
You answered your own question right there. It's a completely new story. Even though the pokemon look like shit, they still work like normal pokemon haha. Same kind of gameplay but with a new, more unique story this time!
Well, yeah. I don't know if they developed the concept correctly/succesfully... but Team Plasma's premise was actually logical. And N is such a cool character IMO. I can't even remember the names of the leaders of magma, aqua or galactic, (that were all awful villians, to be honest) but this one is quite unforgettable i think.
What do you guys think of the possibility of a Emerald Remake for Generation 6? (or 5). It's a speculation that's going around in the fanbase...