The standard rate is actually very reasonable and the alternate cost is an absolute steal, provided that you can afford to pitch a land to cast it
I think this is the most powerful of the various one off green card quality effects but it doesn't have any particular additional synergy within green ramp
Besides tapping for both red and green mana, cards that have both land types gain the extra benefit of being more easily searched for by fetch lands, spells, and abilities
In most games, we're accustomed to casting small creatures
Rarity is a key component in determining a Magic cards value, with rares and mythics typically demanding a higher price than commons and uncommons
A deck that needs a couple of key spells can add black, blue, white, or green depending on what type of card needs to be found and what the deck is doing