Balancing out colors/pairs for final first attempt:
Monocolor target: 66 cards/color
W: +2
U: +2
B: No change
R: No change
G: -3

Multicolor target: 32 cards per pair, 1 card per wedge/shard
WU: -2
UB: -2
BR: -2
GR: +3
GW: -2
BW: -1
UR: +2
BG: +3
RW: +1
UG: -2
WUG: -1
UBR: -1
WBG: -1

Colorless/lands: Used to round out cube size to appropriate level (720 total)
C/L: +3