The Big Mana deck was problematic. Because of the nature of the format (mostly partner commanders), decks tended to have lots of access to cards during games. There is rarely a lack of things to do. So putting a lot of ramp in a deck ends up making it much easier for it to leverage those extra cards. Basically, the big mana deck always ended up way ahead of other decks.

I still want green's association with mana represented in the cube so I'm going to add a lands deck in its place.