I have this issue with my Audible library. After a while of collecting, I find I’m overwhelmed when I finish one and I go about selecting my next read from my queue.
I’ve since combed through and returned what I know I will never read; tastes and styles can change — and Audible has a wonderful return policy. Often I will sample the first couple of chapters and if it doesn’t interest me, I return it. And of course, I’ve gotten way better about selecting what I buy in the first place, so I can avoid having to make a return.
Anymore, I will typically get several books in the same series and gradually chip away at those for a while.