I wish I had not used the word 'most' just welcoming.
Okay, now we're just down to 'welcoming'
Lyceum Folk Club, Newport (S.Wales)
Llantrisant Folk Club(Pontyclun, not Llantrisant)
Halfpenny Folk Club, Gower
Robin Hood Folk Club
Warwick Folk Club
Bedworth Folk Club
Second Tuesday Folk Club (Cardiff)

The above have all been found to be welcoming (even if they've heard me sing before!)