Peace to all,
I am gravitating towards a fixed position as organist in my church. I am now starting to practice the footwork, and doing some exercise after each sunday Mass for the footwork. I am practicing the piece shown below, as my first postludium. I would be interested to hear if any other on forum has got some favorite organ piece suitable for a postludium i.e. playing as the finale of the Mass. If possible post your suggestions with a video
The Fanfare in D by Jacques-Nicolas Lemmens has been my go-to whenever I find myself playing the organ with little time to prepare beforehand. It’s always a crowd pleaser. 
(The recording is mine.)
Thanks DLW, that is a really nice piece of organ music 
Anything by Sarah Hart. She composes some beautiful pieces. Would be interesting how they sound on an organ.
I love her song “You Are the Light,” but there are probably others that would sound better on the organ.
Organ with singing - that is a completely different angle. Would you like a postludium like that?
Oh, yeah, that might not be what you are looking for. You want something that sounds like someone pounding on the keys randomly 
What about this? https://youtube.com/shorts/DiyBzkatC4M?feature=shared
Well, I was asking about your taste. I do not have a firm grip on what the congregation like musically. Oh but one thing I know. I have been playing the electric piano when the organist was not there, and now there is such an amount of encouragement that they want me to keep playing the organ. I actually prefer the piano, since it is closer to the priest so that I have a better feel for when I should play the interjections and so on. In my church they definitely prefer organ over piano