Being able to hold up mana to interact and then dump it into casting something outside of normal timing restrictions is incredibly powerful in Commander, so I definitely think that this card will be a big hit in the format
For example, Wydwen, the Biting Gale is the 590th most popular Commander in the game, which means that not only did the Sultai Mutate deck get the short end of the stick in terms of the number of reprinted Commanders, but the one it did get was pretty lackluster (although Wydwen, the Biting Gale is cute with mutate, allowing you to pick up your entire mutate pile to save several creatures from removal)
Saheeli, Sublime Artificer - more tokens on noncreature spells, plus copy tricks
Dragon Broodmother Dragon Broodmother offers a path to a wide board of big Dragons thanks to its token generating ability
Then behold The Reaver Cleaver