SOPP535: Improving registration on the organ

This question was sent by James, and he writes: “Thank you for your podcast, it has been a great help. I have played the piano for 25 years and the organ at my church for 17, but was only able to take organ lessons for the first 2 years, the rest has been essentially self-taught. Your podcasts have been very informative. 1. my dream for organ playing: I know I will never be a concert organist, but I would like to be able to really make my church organ sound great, and select unique registrations throughout the Mass. 2. The 3 most important things holding me back: a. over the years, I have basically settled for just a handful of different basic registrations for hymns, etc. without much variety b. my church has a relatively small, 22-rank, 2-manual Zimmer pipe organ, installed in 1999, which is almost completely enclosed inside an alcove, and doesn't "sing" very well. The church is the size of a cathedral, but I'm afraid the organ is too small for the space. c. I have never had formal instruction in the theory of organ registration, other than what I have learned on my own. I know the basics of building a principal chorus, understanding overtones and harmonics, etc., but my registrations are still very "boring" in my opinion. Again, thank you for your podcast and teaching, and I look forward to any advice you can give me. -James”