You may be in luck. We are working on a “power user” feature for Winter ‘19 (safe harbor) where the user can ctrl +click (command+click on a Mac) on the item in the navigation menu dropdown list to open that item (e.g. object) in a workspace instead of the left region. Then you could have multiple objects “open” simultaneously.

This lets each user further personalize the organization for his/her needs. (It’s not declaratively configurable by the admin.)

Does that seem like an appropriate solution to what you’re describing?