Nice guys! Some cards that stood out to me where Politoed, Mienshao, Mountain Ring, Training Center, Eevee, and Clawitzer.
Politoed - Looks like it has a deck already built out for it. Politoed's ability King's Song makes it so all Poliwag, Poliwhirl, and Poliwrath's colorless energy requirements for their attacks can all be ignored. So Poliwrath is hitting for 60 and 30 to the bench for no energy, and 130 for 2 water energy. Not to shabby.
Mienshao - his first attack Aero Turn, does 40 and makes you return Mienshao and all cards attached to it to your hand, all for one fighting energy. Maybe this might see some sort of play in a lock deck?
Mountain Ring - This is gonna be a fun card, I can tell already. It protects all benched pokemon from damage from all attacks. It's a god stadium to use if you aren't running any stadiums yet. Example: So in my RayBoar deck, I run Delphox not Beach, so I need a stadium to counter Frozen CityVirbank, why not run Mountain Ring? It protects against Darkrai, Genesect, and Landorus, just to name a few.
Training Center - This card makes me happy. It looks like TPC took some effort to make a stadium that only Stage 1 and Stage 2's can use. Sure, 30 HP isn't great, but it isn't bad either. It gives most Stage 2's the same HP as your typical EX - 170, 180 HP.
Eevee - His ability is it. This card will could be the best Eevee to run if you still play Flareon and Friends. However, now you're forced to run different energy types. Not sure how well this Eevee will be received.
Clawitzer - His second attack is 50 plus 20 more for each water energy attached, with a requirement of 3 colorless energy. So it is the exact same as Keldeo EX's attack besides the name. Might be a good non EX attacker in Blastoise that doesn't get OHKO'd by Druddigon, but it's also a stage 1, plus it only has 100 HP, which is an easy OHKO for Yveltal EX or Mewtwo EX.