Looking at the history of Energy decks across formats highlights the mechanic's unique ability to provide both enablers and payoffs that can be equal parts powerful, unpredictable, and perhaps for game designers, difficult to balance
I always found it odd that often times to play Magic: The Gathering correctly, you need to focus on only one class or race of creature
Most famously, vintage cubes usually feature the "power nine" (Ancestral Recall, Black Lotus, Time Spiral, Time Walk, and five moxes)
Snow Dual Lands are only worth prioritizing when the deck includes cards that explicitly reward snow permanents
The discard aspect of Death Cloud works with the general theme of the card even when it isn't the specific part of the card you want to be using
The sideboard should be taken with a mountain of salt