Mario always and forever.

Eh, the floatiness and tripping really never bothered me and my friends all that much.

Also Brawl get's some browny points for the Subspace Emissary mode and the absolutely outstanding opening theme composed by none other than the legendary Nobuo Uematsu himself.

~Include a Mario Party 3/DS-esque story mode.

~Make the car a separate mode and have classic Mario Party be the main course.

~Include a online mode.

~Bring back the day/night mechanic from Mario Party 6. (Or technically Mario Party 2's horror land.)

~Bring back the ability to change costumes like in Mario Party 2.

~DLC Characters and Boards?

Brawl > Sm4sh > Melee > 64