While the other painlands certainly have their uses, it seems that Llanowar Wastes taking the top spot is due to its popularity in the fan-created Premodern format, and, in particular, the longtime favorite Recurring-Survival deck (which employs the classic combination of Recurring Nightmare and Survival of the Fittest)
The idea is that by putting all the Grim Haruspex effects together, you should discover plenty of cards you werent aware of for your decks, especially considering singleton formats like EDH which benefit from redundancy
What Is a Chaos Draft
But I still think Akroma's Will deserves the top slot because its effectively a modal spell: Its a protection card and a finisher since it effectively makes your board unblockable and gives it double strike
Avatar: The Last Airbender (TLA) also brought it back, where it featured on creatures like Giant Koi and Mongoose Lizard
Cast Hermit Druid and activate it The Hermit Druid method takes just five mana after Survival, while the backup plan takes eight