Coming from someone who's not that big on anime, I'm particularly fond of Digimon's first season. Even though it's simple, the fact that it focuses so much on the problems that each of the Digi Destined have is what makes it unique- I don't think anyone's gone through childhood without at least one of those problems.
I haven't watched much Haruhi Suzimiya,and it's definitely pretty good, but I can't help but feel it's kinda overrated.
Wasn't that season started before the card game was? In any case, yeah, they didn't follow any actual rules, but frankly they've broken so many rules throughout the series for the sake of plot that it doesn't matter.
I really don't think Super Man 64 is as bad as everyone makes it out to be. It's a terrible game, yes, but it's not 1/10 terrible. Also some of the games you guys are listing (Mario Party 8 for example) are at the very least mediocre. They're anything but the worst game ever.
Cheetahmen II is the most literally unfinished game I can think of. Although it was never released, they were almost ready to do so, so it definitely counts.
After the game's fourth level, there's literally no way to get to the fifth level. Defeating the boss just makes you stuck there forever. If you hack the game, you can get to the fifth and sixth levels- After beating the final boss in level 6, there's NO ENDING. It's just like after level 4- You're stuck there forever.
In Banjo-Kazooie: Nuts and Bolts, there's a level called Banjo Land, which is a museum that shows stuff from the first two games. There are pictures on the walls from BK and BT, and some of them show beta content. When the textures were ripped, it was found that some of them have the IGN watermark on them, so Rare just took screenshots from IGN and put them in their game.
Super Mario Galaxy 2's final boss wasn't that disappointing. Sure, his final form was way too easy, but the final boss as a whole was at least somewhat tricky. Galaxy 1's was way easier as a whole and it wasn't even that epic.