This LRR pre-release stream is already amazing <3
Green decks and decks that want to use mana rocks don't look the same and don't play the same (unless you're playing super ramp and trying to hardcast Eldrazi). This is a non-issue. Plus "color X doing thing Y it doesn't normally do" is the name of the game when you're using cards from all of Magic.
The principle is the same- you're giving everyone the ability to play "green" without actually having to play green.
Green decks and decks that want to use mana rocks don't look the same and don't play the same (unless you're playing super ramp and trying to hardcast Eldrazi). This is a non-issue. Plus "color X doing thing Y it doesn't normally do" is the name of the game when you're using cards from all of Magic.