I don’t have any experience with art therapy, either in or out of a church setting, but one thing I would take into account would be, “Who is my target audience?” ie, who am I trying to reach? I’d consult with some of those people, to see what their needs were, to help gauge interest in my program, or to build it to be attractive to them.
However, on the subject of “art + spirituality”, I travel frequently to a (not-Catholic) church that periodically hosts icon workshops. Not necessarily
one of these, but just to give an idea. When there’s not a workshop going on, a lot of these people will meet and work on personal projects. The ones we do for the workshops are in egg tempera-- there are other people at other churches who do similar things, but in acrylics. Since I’m not local, I don’t have a good grasp of all the local church art things going on, and who’s part of what group, and how the groups overlap, but my impression these casual gatherings fluctuate between “structured” and “personal”.
So, this sort of thing can be very intense, and it’s appealing because of “learning about art”-- learning how to build egg tempera (or acrylic gouache) into layers to achieve an artistic effect; and appealing because of “spirituality”-- growing a connection with who you’re trying to depict, and trying to be in a constant state of prayer while you’re doing it; and appealing because of “history”-- learning how to see/read/interpret iconography, and the meaningfulness and symbolism of line and color and such. And at the end, you have a really beautiful piece of art, which is much more than art, because you’ve put yourself, flaws and all, out into your piece for everyone to see.