There is no easy workaround to this, because the way TV work is based on template, instead of document group.
ONe thing that you can do, use @INHERIT binding for your TV_Content, and use MODx folder structure to let the value of parent folder being inherited through its child docs and folders. With this, if you have 3 different set of content for TV_Content, then you need to create 3 parent foldersm and put all your docs/folders accordingly to follow thich TV_Content format that you want to use for each of that new docs/folders.
Hope that helps.
PS: That’s a way to go have a default TV_Content. It’s one of best practices that each MODx users have to use for their new site design using MODx