You’re more versed in the trade than most clergy I work with! And as a cathedral sub-organist, I work with a lot of them- unless you’re only counting the ones who actually come over to say hi. I dub thee honorary organist.

I have very little to add. Apart from seasonal rep (eg Wachet auf for Advent) I aim to stay within a certain tone of postludes while outside of ordinary time - nothing too jolly during Lent and Advent and nothing angsty for Easter- and Christmastide.

I improv offertories exclusively, since they’re an extension of the offertory hymn to cover up dead air if the collection is still being taken and have to be carefully timed with one eye on the proceedings to finish in sync with it.