If we're making this "the best it can be" now, I would suggest 2 each of the dual lands for R/G, R/W, R/U, G/W, G/U, and W/U, and 2 each of the basic lands of Mts, Forests, Islands, and Plains. However, I'm adding another "mana fixer" - the almighty Krosan Tusker.
(Red)
Fling x2 - Ransac x2...