Theres also the fact that the distribution for Enchanted cards is roughly 1 in every 72 booster packs, so finding one in a booster is definitely a rare occurrence, even if youre buying full, 24 pack booster boxes
Given the generally low mana-curve in Modern, cards exiled with the pirate monkey will usually be castable with the help of the Treasures and almost any card is worth playing as it simply generates card advantage
Mana elves that tap for green mana often charge less than $1 per copy
Shared Summons is probably the best one, as it can get both creatures, and cards like Eldritch Evolution or Eladamris Call can be reasonable choices, too
That said, there is an audience that wants to see incentives to play the fewest colors in Commander and those kinds of answers are not going to be properly seen in a Standard-legal product
Its especially strong in decks that can bounce or flicker it, or in ones that don't plan to let their opponents play their next turn at all