Perhaps we can kill two birds with one stone (or hotkey...
)
Use "," and "." to cycle though commanders when a commander is selcted (limited to one province or not?) and to cycle through provinces when a province is selected. Though I'd rather be able to cycle through recruitment screens for all my provinces, I find that F1 gives enough info on the provinces for the most part, at least the info that I can't see right away on the main map.