Church Service in the Cotswolds?

I happened to be in Blockley on a Sunday in May 2017 and attended the church service at the local parish church. It was well attended, and people seemed friendly. Blockley is an attractive village.

If music is more your focus, I'm not sure Blockley would be your top choice. The church in Chipping Campden has a music festival each May. I haven't attended it, but its promotional materials are impressive. You can find out more by googling "Chipping Campden Music Festival."

Are there any not nice, unfriendly churches?

Google seems to show that there is a church in Broadwell, but the timetable for services as far ahead as next May will not as yet have been published. A communion service will have more music than a prayer service, generally.

Years ago we attended a evensong service at St Mary's Church in Fairford, south of Burford. We arrived early and were the only people there. An older woman arrived first and she took us under her wing until the minister and a few other people arrived. We had seated ourselves out in the main seating area of the church. But Aunt as we called her moved us to the front into large seats arranged in a circle. The minister asked my wife what religion she was to which she answered Episcopalian. He said good you set there and pointed to a seat. He asked me and I said Baptist. He said ok you sit here by me and I'll tell you what to do. He explained we were setting in the seats that monks used in I think he said in the 1300's. It was a very small group of people with no music but we enjoyed it very much. The minister and Aunt explained the history of the church. It was a great experience. When the service was over Aunt told us where see lived and invited us to stop by for a cuppa if we were in the area again. One of my regrets was that we did not take her up on her invitation.

By all means find a church and attend.