When your potentially blasting a pair of medium pokemon each round, then yes i think 150 gold is a good starting point.So 150 or 50 gold?
We should likely also keep in mind, that since pokemon lacks shields, then ranged attacks like these will be Super Effective.
I think it would balance with how the pretty powerful Onyx is found in a cave?Hmmm, that sounds better yes. Also swamps rarer than mountains. Will do.
I'm thinking of adding them at the cap too like the Onyx with 1/month rec limit.
But being allowed to recruit 1/month is likely a good call.