Harmonized Crescendo asks you to go shields-down to refill your hand, except not really, because its at Instant speed, meaning you can do it in response to a wrath or after blocking or just before you untap
The sacrifice is a choice you make during resolution
As far as expensive cards go, there isnt a ton to talk about
In a deck filled with one-power creatures - 10 of its 35 creatures have base power one - Zinnia can often be a three- or four-power flier by the time it sticks on the battlefield, immediately making it much more desirable than its 1/3 base stats would suggest
Streets of New Capenna is a huge set, thats for sure, and the cards range from complex to more complex
Honorable Mention #1 (#13 Overall) - Biophagus This two-drop 1/3 can tap for any color of mana to use for anything, so it's already better than the smaller and defender Sylvan Caryatid