Here’s something that happens to me at least once per week.
I open my project and start placing assets in whatever level I’m working on. I do this for about 45 minutes to an hour, and decide to play through the level I’m prototyping. I start a Standalone session and there, in my starter level (instead of in whatever map I was actually editing), is the asset-structure I just built. I realize now that EVERYTHING I just did was added to the Persistent Level, because it’s automatically selected, rather than the visible sub-level. So I open the Level viewer, focus on the visible sub-level I’m ACTUALLY working on, and Ctrl+M all of the assets I just placed.
It would be so much nicer if, when I saved and closed the project, it would re-open with the sub-level that I last had focused on-save STILL FOCUSED. I have very little, if any, reason to actually place actors in the Persistent Level and I imagine that’s true of most people USING a level-streaming setup. e.g. if I make visible “Downtown” and I set this level to focus, when I save and re-open the project, “Downtown” should be not only visible, but focused as well, so that I can continue working on IT rather than my (99.97% empty) Persistent Level. As it is now, while visibility settings are saved between sessions, focus never is.