I just got to thinking about my favorite Marian hymn, Hail Holy Queen, since we are gearing up for the Assumption, and remembered a little trick I've used that might be of interest to some organists out there.
This particular hymn has a very wide range--low at the beginning and high at the end. In older books it tends to be written in C Major; in newer ones, B-flat. This latter key, however, is too low in my opinion, particularly when the beginning of the verse is factored in. So here's the quick and easy solution: change the key signature to five sharps and simply read the notes on the page; they are right where they need to be. Only the accidentals need to be adjusted.
Now, generally, I find the trend of lowering hymn keys to be an unfortunate one, a consequence of a lack of truly beneficial musical education--which would instruct in the art of singing well, rather than simply putting children on stage to scream their way through Christmas carols in a manner more similar to Sprechstimme than anything else--in most places. (Before you pounce: There are many schools teaching music well, but many of them, if they're high schools, have to work miracles, since no real foundation is laid in the earlier years. But I digress.) However, some hymns are simply quite difficult to sing, and this may be one of them. The key of B Major seems to offer a compromise so that all voice parts are reasonably happy.