Hey, I noticed that collapsing the context list, you lose a sense of how many tasks are in a context. I like apps that add a show me what I need sensibility to them. I think it would be useful if you could include a number of next actions indicator on the header, and maybe a little color block to show the next action with the lowest due date nearness. This way, you could collapse all of your context headers, but still get a good sense of where the bulk of your work lies, and you don't have to expand every context to remember how many tasks are in there.

This would give you a nice quick at a glance overview of your next actions. I think this would help in setting your work priorities, weekly reviews, etc.