They can be solved fairly easily, and, unless combined with the other half of their combos (proliferation of counters, Mycosynth Lattice, Wheel of Fortune), dont have a huge impact on the game for more than a couple of turns
The new version does not change any fundamental tenets of the format, nor is it a change in vision
Have you played any of them yourself
If you've constructed a deck to contain a sizable number of Spirits, this allows you to immediately swing a game in your favor with cards that could return each Spirit in your graveyard to the battlefield like Living Death, Patriarch's Bidding, or Twilight's Whisper
Disclaimer TCGDex is an independent, third-party application and is not affiliated with, endorsed by, sponsored by, or associated with Nintendo, The Pokemon Company, Game Freak, Creatures Inc., or any official Pokemon franchise entity