I've added 3 votes to this one. I wanted to suggest this myself, but I see you've made the scenario as I had it in my mind.
My scenario is a little different though, perhaps you could change that inside your post to make it a bit more general.
I want my inbox to be my main priority list, without any due dates. I have lists for school subjects, work projects, personal projects, etcetera. However, there are a few tasks that really should have my attention, but they don't get that as much as they should, as they're split across multiple lists.
I would like to reflect/copy/shortcut these priority tasks (instead of starring them (which is a good suggestion though..) on my inbox list, instead of duplicating them without a sync.
This functionality, as you describe it should be essential for Wunderlist!
Again: 3 votes!
I completely agree with this. A simple tasks, such as "Find supplier of X" can be split into "Searching", "Requested offers" and "Awaiting choice of supervisor". If you've done 1 and 2, you have in fact done the task, but can't check it off as you need someone else's input.
In that case this task would mess up the other tasks which do require your attention.
For now you could use pre-pend tags, such as #1-Open, #2-InProgress, #3-NeedsReview and sort alphabetically. This way all things that are done by you, but not completed yet could be at the bottom and those that require attention are at the top.
3 votes! If I could give 10, I'd do.
Not necessarily ToDo's, but primarily the size of list names. I've got many lists, even some in Folders, but I want everything open. Even on my big 23" 1920x1080 screen I cannot see all lists in one view. I have to scroll. If I could decrease the size by about 20% that would be great.
Suprisingly, this still hasn't been made possible..