vim-addons is the tool used by users and local administrator to manage Vim addons. It is shipped in the vim-addon-manager package. Using it the state of an addon can be changed to one of installed, removed, disabled (i.e. prevented to be loaded even if available somewhere in the Vim runtime path). The state of each addon can be changed both for a single user (playing with symbolic links in ~/.vim) and for all system users (via /var/lib/vim/addons/, which is contained in the Vim runtime path).
For more information about vim-addons see its manpage: vim-addons(1).
Since vim-addons is the recommended way of managing Vim addons available in a Debian system, you should instruct your package users about it. You should hence put a Recommend: vim-addon-manager to your addon package and provide a suitable README.Debian with basic instructions about how to use it. See Section 1 for a template where to start from.