Creatures dying will generate energy, but even a few cheap lands like Evolving Wilds and Terramorphic Expanse pull their weight when you sacrifice them.
That said, there are plenty of Cube decks that end up playing a lot of basic Forests
Basically, it is just better in every way
Just like Jhoira earlier, I like him casting fat stuff for five mana, like Insurrection, Eldrazi Titans like Ulamog, Archangel's Light, Plague Wind, Searing Wind, the Ultimatum Cycle like Genesis Ultimatum, Conflux, Apex Devastator, Progenitus, Avacyn, Angel of Hope, the Ancient Dragon cycle, and loads more
Even if the curser doesnt then wipe all the now measly minions from the cursees board, it becomes so much easier for anyone else at the table to destroy them, not to mention just attacking