Once Bolas is defeated, Vivien does some planeswalking and some soul-searching until she decides to travel the multiverse and try to prevent other planes from breaking the balance between nature and progress
It doesn't copy whether that creature has any counters on it or Auras and/or Equipment attached to it, or any non-copy effects that changed its power, toughness, types, color, and so on
Apart from perhaps removal and counterspells, you wont feel like youre missing out on much of what you need to be successful
[srcylink]Stromkirk Occultist[/scrylink] from Eldritch Moon (2016) tried to push the mechanic, but the environment was quite hostile to anything without an ETB effect at the time
These designs are Universes Beyond at their best, and frankly, much better than many top-down designs from recent Standard sets