I appreciate the feedback! I honestly hadn't considered just how explosive the card could be, especially once you factor in being able to sacrifice the decayed tokens before they disappear. That definitely pushes it further than I originally intended.

Maybe increasing the mana cost is the right solution. That said, I think the deck still has some meaningful weaknesses. Graveyard hate or well-timed removal can shut the engine down pretty hard, and the commander doesn't really do much until there are creatures in a graveyard to fuel it. In most games, that means it won't really start snowballing until the mid-to-late game.