I know my Debian, thanks
What do you accomplish by removing calibre's dependecies as well? Even more unmanaged files spread around the filesystem?
What if some of those dependencies are needed by some other (future or present) package? You may not even be able to uninstall the deps, unless you "go manual" with that other package too.
The only clean solution is to make an updated Debian package (which often requires updating the dependencies too).