Created a new custom post type to store predefined replies

I need to confirm few things:

1) It save revisions. Do we need them?

2) I have added it using add_submenu_page rather than register_taxonomy argument 'show_in_menu' as the latter doesn't show "Add New Predefined reply" in "Supportflow menu". It solved this problem but "Edit predefined reply" page still doesn't shown in menu.

3) It uses WP publish metabox. It has some additional features like "Visibility" that we don't need. I was not able to find any API to remove parts of publish box. So either we can remove this box and create a new custom box with our options or do some JS fix to remove unwanted option. Which is better option?

4) All Predefined replies shows "View"  option even when 'publicly_queryable' is set to false. Is I set 'public' to true then "Add new predefined reply" say invalid post type. So, how to deal with it.