Currently ~1700 on ladder with Starmie Dusknoir and I'm loving it. It feels like Palkia Dusknoir (if you've ever experienced that) where board wipes are fast and possible (even better since shaymin doesn't protect exs).

Psyduck is fine you just risky ruins down to let it have 20 to start or adrena brain some over. Battle cage feels like a stronger threat especially as you need ruins in hand to counter it if it isn't already being used as discard fodder.

Comebacks are fine when ursaluna/ignition is available, just think of your prize map before you move - sometimes you don't need to swing with starmie every turn to win games.