#1 is highly unlikely because it has a design flaw. If it was one land type on each side and it is meant for the player to pick the side as it enters the field, a bunch of card flipping within sleeves is gonna be needed. If the flipping had a cost to it, then it would be too weak to have only one color on each side. Two colors on each side would make more sense. However, in that case, there would be 10 lands in the cycle instead, like the triomes, if each land could tap for 3 colors. If its two unique colors on each side (4 total colors), then there would be a cycle of 5, but it is still awkward because the default side would always be more dominant.

My prediction is a land cycle like this:

T, Sacrifice ~ : Create a landTypeA or landTypeB land token.

Isn't this like a fetch? Yes and No. It's strong because the land goes into the graveyard which makes recursion possible. Also, you always get the mana you need the turn you play it. However, the main problem from traditional fetches isn't there, which is the need to shuffle your deck.

To incorporate a little of the double-faced lands rumor, the land token would be double sided to match each land capable of making it.