I know many people and I like to talk with them about things, but each person offers a different tenor of sounding board. I am tempted to make a catalogue for people and what we've done before, but it should be simpler than that... i ought to Dreyfus it: if I take a moment to judge a candidate playtester, I will know whether I feel good or bad about it. About them playtesting, that is.
[ A. There is a point at which some specific feedback is needed, which may not be provided from every source. (In fact, never is.)
B. Consider all sources of feedback as a Marie Kondo-like intuitive process. Choose according to gut feel, and reflect on how it went. Was the feedback actionable? Was I hurt? Did it distract me from what what really matters? ]