If there are two of these on the battlefield, each of them will modify each draw (after the first one if during the draw step) and will cause the player to discard or to mill a card
No matter what you cast, there will always be value with Rashmi out in play
Masked Vandal Masked Vandal sees some Constructed play in decks like elves as a typal way to get rid of artifacts or enchantments
The 4-mana restriction to prevent you from drawing when an opponent plays a noncreature spell is so, so expensive that theres basically no way theyll even be able to pay
Adding the Song of Rest option means that in those situations, you could an ability that is far more useful, and thats pretty nice
With Hangarback Walker, they cant just ignore it because its threatening to grow and take over the game, so they have to kill it as soon as possible but then you get that value on the way out