Quote from Pinenutt10So, if I'm understanding you correctly, you'd be willing for them to make a "Sixth Color" for a set, if not a block?
Honestly it might be a good way to go. It helps drive home the focus on the mechanic and look like it's something more than just a casual after thought for activated abilities and fresh new land walking keyword.
While you don't want to make it purely about Snow mana, a good 15 or so cards with it in their casting cost, with maybe an 'all snow' legendary creature could make for a cool set.
Maybe have some cards that say "If was used to cast NAME, do THIS." and maybe other cards where you got benefits for not using snow mana, or where worse if you have snow lands out. Like Karric said, it's a tough like to walk considering how snow lands are handled.