Neil, I just saw this picture of an open cabinet with wallpaper in the back.

As I was looking at it and thinking how it draws your eye away from the clutter in the open cabinets.

So I was thinking what if you painted a can of paint in the left hand corner of the room tipped over by the ceiling with colourful paint coming out in a wild rainbow of assorted colours.  Here's a picture (second photo shown) that gave me the idea, although the paint colours they used are dull.  The paint would continue right throughout the back of the cabinets.  Could always ask the congregation for leftover paint or go to your local recycling center to pick up paint for free (if that's available to you in your area).

You could still have room across the top of the wall (height of your paint can) to put your lettering across.