The white card in the cycle, Retreat to Emeria, either gives you a 1/1 Kor Ally creature token, or gives your creatures +1/+1 until end of turn. At 3W, it’s more expensive than the Green Retreat, which is 2G. But, Emeria's Retreat gives you some card advantage in the form of tokens, with the alternative option to pump your creatures, as well.
One interesting trick involving this card has to do with fetchlands. You can hold onto a fetchland and not activate it until during your opponent’s turn. This way, in combat, you can sacrifice the fetchland to go get a land and trigger Landfall. It's a cool little combat trick. Still, even in formats running rampant with fetchlands, as a 4-drop Enchantment, it doesn't have enough immediate impact on the board to see competitive Constructed play.
The abilities on this card are relevant that they should see some play in some cool brews. Perhaps a deck that uses Oblivion Sower to full effect could benefit from these Landfall abilities. Or perhaps, there will be some sort of control deck that utilizes this and other Retreats. (Update: There is a deck list out there called Full Retreat Control that runs the full four copies of Retreat to Emeria.)
There's also a cool three card combo with Retreat to Emeria that involves Perilous Forays and Lotus Cobra. This combo lets you pull all of the basic lands out of your deck. While a Perilous Forays deck isn't extremely competitive, it's at least fun. Retreat to Emeria is a fun little card that is definitely worth considering.