Hi Alex, I think it would be difficult to express an additional hide state in the UI without it getting complicated.

You can avoid unhiding everythying currently if you use the scene browser to do your unhiding instead of the Edit > Hide command.

Also if you use Ctrl+click on Edit > Hide that will do a "show subset" operation where you can show just some of the hidden objects instead of all of them.

Maybe if you want something totally out of your way for an extended time you could export it out to a separate file and then delete it from your current one.

- Michael