JJ...
There are two mics, I think. No "mixing".
Russell's situation actually sounds very similar to my situation. At my home church, we, too, have a traditional service comprised of the spoken word and congregational singing with an electric organ for accompaniment in a sanctuary that seats about 120. We have two mics: one at the pulpit, and one for announcements.
Most of the time there is no mixing. We do have to adjust the pulpit channel for different preachers, but that's a once-a-Sunday deal at the beginning of the service.
Even so, there are special events such as weddings and funerals. At these, the families often want special music, vocalists, multiple speakers, etc. When that happens, I will bring in my bigger mixer, a snake, extra microphones, etc. and patch it into the system.
As for what I wrote before: I wrote it not only for Russell's benefit, but for anyone in a similar situation who might stumble across this thread (or any of the dozens of similar threads posted in this forum
). Therefore, I included some things that others may want to consider.