Easier folder navigation, hierarchy

Can the list of folders be improved, please?
I file emails away by subject and very often various sub subjects. When searching or filing in K9 all I get is a huge, long list of folders. Instead what I’d expect or lije is to show level 1, then level 2 and so on making finding folders what I need to search and where I need to save vastly quicker and easier and less chance of making a mistake.

EG. A booking for a theatre could be filed in:
Entertainment → Theatre → Paladium → Pinter
Current view it is hidden in a huge list, with long names/addresses for each.