The first Mario Party I owned, and overall kind of a mixed bag. There's a handful of real standout minigames, but a ridiculous number of random and button-mashing ones (3 of the 6 Battle games fall into one or both categories).

The new capsule item system is unique but pretty hard to strategize around, given that if a capsule is placed on the board, all players are eventually equally likely to deal with its effects, whether positive or negative. This tends to lead to boards becoming organically-created minefields of hazardous spaces to avoid, which is an interesting dynamic, but less strategically beneficial to individual players than 6 and 7's character spaces (and it doesn't help that the board maps themselves are all pretty same-y).

The increase in side modes is interesting, though, with the Mini-Game Decathlon becoming a staple for alternative competitions, the bonus sports minigames being pretty fun, and the story mode feeling actually distinct from the main party gameplay for the first time. Overall, I'm probably slightly more inclined to revisit this than 7 due to its unique item system, but 6 is still going to be my go-to GameCube Mario Party for the foreseeable future.