I forgot to mention two other things I hate about new Gens starting.
1) How long it takes for new information to arrive. I'm a sucker for new info, as I like to be informed. When a new Gen is in the works, it feels like forever when new info starts to leak out. It's around that time the fakemons and such start to surface, so it does tie into my previous hating false information statement.
And most of all... THE WAIT!!! I'm not impatient (usually), but I can work myself up when waiting for a new game, and the wait seems twice as long as an end result. I've always been that way when it comes to games, especially since I'm picky about that. But the wait can really tear me apart.