A Trim Paths mode that only affects Stroke while leaving Fill untouched will be a good addition.
I'm looking at the Trim Paths, Trim Multiple Shapes Drop Menu as a guide for the UI-UX.
So, right at the top of its UI, above Start, we have a Drop Menu, Trim Path Affects ...
with the following Drop Menu Items -
Stroke Only
Fill Only
Stroke and Fill
and Stroke Only wil be the default.
Very Advanced After Effects Training | Adaptive & Responsive Toolkits | Intelligent Design Assets (IDAs) | MoGraph Design System DEV