Finally Blender 2.8 makes this time consuming work a little bit easier ^^

While I'm watching the exhaustion you have to put into the efficient use of UV Space, I'm really glad that Blender 2.8 has made this a little easier, as it now allows you to edit multiple objects at once without having to make use of this painful workflow.

But 2.8 still isn't perfect and needs some UV improvements. Fortunately, there are several very helpful addons that can help to achieve this.