Surprise 1: The scriptures played almost no part in the service. There were two very brief (and very familiar) quotations from Hebrews, but these were simply there to act as the springboard for the preacher (who read the passages himself in the context of his sermon).
Surprise 2: I thought that Protestants believed in irresistible grace and despised 'works-righteousness'. But a hymn (sorry, worship song) that constantly repeated 'I choose to follow you' (or something like that) sounded almost Pelagian.
Surprise 3: There was quite a lot of prayer, of the extempore making-up-prayers type that I am no good at. But the Lord's own prayer was clearly found to be deficient, because it didn't feature at all.
I'm not criticizing, merely recording my own surprise. Perhaps there are perfectly good explanations for all this.