Typically, anime-art variants of cards have been rather lucrative, but when thats the only option
Sadly, the ability to get non-Forests to fix your color concerns likely will never come up since there are so many good colorless lands available for mono-color decks to take advantage of
you may look at the top card of their library any time, you may play the top card of their library, and you may spend mana as though it were mana of any color to cast spells this way. We already wrote about this floating eyeball in-depth, but the long and short of it is that you can always choose the best player for whatever you need, and thats the kind of flexibility you really want in any deck, let alone in your commander
It's a win win
There are 103 Sagas to build around, pretty tight in a Commander deck, but he'll get loads of play despite it
Wizards of the Coast has published two additional articles today on Aether Revolt matters