You have Overrun effects to make your mana elves useful late game and they massively outshine this kind of thing
This is a great mana sink when you dont have other plays to make, but if players cannot make the most of The Earth Crystals activated ability, then the Crystal is not worth playing
Ramp Both red and blue struggle with mana acceleration , especially in multicolored decks
Tovolar, Dire Overlord The card draw ability on Tovolar, Dire Overlord is super powerful, and although the typical Tovolar werewolf EDH deck is a bit midrangey, there are over 40 wolves and werewolves in this Gruul commanders color identity at 2 mana or less, and some of those are pretty awesome, like Duskwatch Recruiter, Kessig Naturalist, Mayor of Avabruck, and Werewolf Pack Leader
3) Kaldra Compleat Kaldra Compleat is the second (and much angrier) coming of Batterskull
Each may be activated once each turn