Wow, sounds like it was a lot of fun. Makes the new events seem boring. At least we can use wi-fi to get them now, but they're a lot less eventful. Maybe because of the hype from pokemon has died down over the years, I guess.
I know what you mean. I've seen Shiny Natu, Corsola, Sudowoodo, and Bulbasaur in the frontier, and it was annoying. I try to hunt shinies, so it bothers me a lot. I get most annoyed by the insane luck the AI gets though. In the subway's super single line, I lost at battle 48 because of crits. I also lost to Palmer in Platinum because Cresselia confused my Metagross with Signal Beam, and I never hit once. Next I took out Gyarados, and Ice Beam froze it. It never thawed.
I loved Mt. Battle in Colosseum. I remember how long it took to finish it, only to realize you only get Ho-oh with the in-game team. It was still fun.