Basically, any cards or common game plan that messes with several of peoples lands or the mana they produce should not be in your deck if youre seeking to play in the first three brackets
The Arena version feels a bit weak comparatively - while that isnt a total dealbreaker, it does make you wonder what the thinking behind the move was
And, yes, that means Jace, Nissa, and Nahiri are the three Planeswalkers in this set
Thankfully, looking through the list I'd say that WotC did the best job here
Reclamation Sage is a classic ETB Naturalize effect to get rid of enchantments or destroy artifacts, and has the elf subtype, which can be relevant in elf typal decks going forward, or even in the sideboard of green decks in general
Until end of turn, target creature you control has that base power and toughness, becomes that creature type, and gains that ability