It's a fair criticism. We really wanted to nail the very common use case of: "I put a small table in a blog post and I want it to be sortable and look good."
But I think you're right that it would be great to have a pairable tool which adds filtering and possibly another which adds client-side pagination.
Tere's also "keep my table headers frozen" functionality that's often requested along sorting, filtering and pagination.
This was a huge point for me when using the old tablesorter script. They had a plugin called StaticRow that would allow you to add the "static" class to a tr tag and it didn't change when sorting. Did you guys implement that too?
This library supports that if your static row is the header (uses th tags).