We don’t use colored mana symbols to strengthen or weaken cards very often, since usually the fundamental problem with a card being too strong is how much total mana it costs, not how reliably a multicolor deck can cast it. If we change a card from 2G to 1GG, it’s still just as strong in the heavy/mono green deck as it was before.

Instead, we use colored mana as a knob to tune how many different decks have access to a card. If we want a card to be a reward for going heavily into a color, we’ll give it more colored mana symbols. Usually we’ll do that with “rate” cards, which are just powerful but not very build-aroundy. Conversely, we make a lot of the Johnny/combo cards a single colored mana, so that creative deckbuilders have more variety in what they can do with them.

-Ian