Just like the title says, I would like to be able to have other outputs besides sawdust in the sawmill, like bark from farmer's delight when stripping a log.

Currently using the latest release of the Fabric version and trying to add a recipe with KubeJS to strip logs and leave stripped logs and bark behind.

Thanks for your suggestion.
I will implement it in v1.4.4.

v1.4.4 will be released after I have back-ported the update to 1.19.2, 1.19.1, and 1.18.2
For details see Sawmill with other secondary output item [v1.4.4 and newer]