Same total mana value, and they both dish out counters when they attack, though Expanding Ooze needs a modified creature to target
There is a great balance within this deck as it has 28 creatures and 24 instant or sorcery spells, many of which include an X-cost
The standout cards in terms of value include Aurelia's Vindicator, Anzrag the Quake-Mole, Vein Ripper, Trostani, Three Whispers, The Pride of Hull Clade, Vannifar, Evolved Enigma, Massacre Girl, and Rakdos, Patron of Chaos
You can go Voltron (and that's likely where most people will go), but you're in colors that support pillow fort, prison/stax, or even just plain stompy
As a mechanic I think it's fine, though it does require you to be either getting some good effects from the card itself or rebuying some pretty great abilities to be worth the tempo loss