I received many libraries inquiring about the same, and a few libraries who'd changed over.
Four out of our five branches use a modified BISAC type of organization. The BISAC categories were worked on by a committee for several years before we started using it. It has since been whittled down a little when we found that certain categories just didn't have many materials in them. We utilize it for Fiction and Non-fiction. I know that at each branch, circulation numbers increased by about 20% when the branch reopened.
The Fruitport District Library moved away from Dewey in 2017. We use BISAC but after a couple directors and different circulation staff the call numbers have gotten very confusing. My goal this year is to create some kind of order among the chaos.
If you do switch, put in place a cheat sheet for call numbers so there isn't confusion.
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I also contacted a library in Arizona who used what they termed "ShelfLogic". "Sure; I’ll be glad to share our nonfiction categories in ShelfLogic. This is a working document and doesn’t have the best formatting, but it has all the call number sections included with some descriptions. We really enjoy using ShelfLogic and our customers are overwhelmingly supportive of it as well."