Personally I prefer the kebab/dot conventions simply because they allow for easy "navigation" with (ctrl+arrow keys) between each part. What are your preferences when it comes to this? Did I miss any schemes?
Underscore to delineate different parts, hypen to delineate words.
Like:
my-resume_draft.pdf
And to make it consistent and easier to reuse parts for project names and such, I have a command line utility written for it. It caches the parts and uses a template system (support for generating current datetime in parts)