Modern, Commander, Legacy, and Vintage frequently have Urzas Saga in their metagame discussions
We can see there being some neat interactions with Sagas, MTG planeswalkers, poison, or tokens
According to current trends, Sphere Grid is going to get even more expensive in the short term
Being a multi-colored creature that cares deeply about tribal synergies means it can really only go in one deck and it doesnt have room to grow from there
For example, ward cant stop [c]Diabolic Edict[/c] because Diabolic Edict targets a player, not a creature
Alternatively, Pristine Talisman gives you the same thing for a few more cents and doubles as a mana rock :D High Market got reprinted so it's super cheap now, Pious Kitsune gives you another white tap-to-gain-life