I sell sound effects an music on a non-exclusive basis. I was confused about which road to take as well, which is why I created a numbers experiment, tracking non-exclusive sales from various companies and calculating what the hypothetical amount would have been if sold exclusively. It started with one year, but I’ve been doing it for a couple years now. The result so far always turns out to be more profitable on a non-exclusive contract.
The market keeps evolving though For example, AJ now allows authors to adjust the price of their products like P5 always has. That changes the numbers from the original calculation. Libraries are also offering more licensing options now too, like single-use or multi-use.