I'm suppose I'm intruding here as I'm Catholic, but I used to be Presbyterian.
When I became Christian at the age of 28, I joined a Presbyterian Church because I'd been baptised Presbyterian, but there was a bit more to it than that.
A brief background first - I was only baptised Presbyterian as my father lost his Catholic faith. He married an Anglican, and they got married in a Presbyterian Church (talk about our mixed up Western Christendom!). I'm not sure but they probably gave an undertaking I'd be baptised Presbyterian when I came along almost 9 months to the day later.
But they never went to Church themselves other than the occasional Christmas, Easter, weddings and funerals as far as I can remember, but packed me off to Sunday School when I was a kid. But I never really felt accepted and got out of it when I could. By the time I was 15 I was atheist. I certainly didn't have a strong Presbyterian background (or Calvinist if you like).
I became an atheist from around the age of 15, but became Christian at the age of 28. At that time I was in a crisis state, but seemed to get this persistent sense I should go right back to the very same Church I was baptised in. So I did, and accepted Chist at that church. But I soon gravitated to the main church in the parish (there were 3 churches in the parish).
To cut a long story short, what kept me there for the next nine years wasn't a strong "Presbyterian" conviction, but a very effective, almost brilliant pastor, his family including his wife and five very capable sons, and a bunch of agreeable young people - in other words, a happy church. There was even a gym under the church. And very clear and strong Christian teaching.
The time came for me to move on, but there were other factors at work at that time as well. In due course I became Catholic (something the pastor predicted anyway, saying "I think God might want you to go back there" - to the church my father had abandoned - again there's a bit more to it). While I've settled in well in my Catholic faith, I still remember that particular Presbyterian Church good memories.
The moral of this essay - it was the PEOPLE who made the church!