Remove/Add items from Custom Lists Easily with Checkboxes (Suggestion)

My suggestion is maybe we can have something like checkboxes. For example, if you have ever used Youtube playlists, when you add a video to a playlist, there is something like this: 

It is easy to see which lists you've added the video to, remove it easily, etc.

Removing a title/actor from a custom list is harder than adding it. We have to go to Custom Lists > choose the list > edit > delete > save.  (not voting lists).

Unlike removing titles from the Watchlist. We can see if the title is in our watch list from the pencil item instead of the '+' and simply delete it on the spot.

But to check if the title/actor is in a custom list, move it to another list, or remove it from a list is a bit tedious.