How to deal with mega-dropdown menus with inconsistent content?

Question

Context: desktop site which shows data. The main menu has from two to four levels.

Without the possibility to change the page content and the menu architecture, we have to optimize the menu view. The current site has an old-style drop-down menu, and every level is opened at the mouse over.

We propose this kind of visualization and disposition (see image):

but when one of the second levels has not deeper levels, there is too much blank space and the items are not so visible.

How to deal with mega-dropdown menus with inconsistent content?

Answer 1

There is not very much you could do without changing the architecture of the menu.

You could change the way you have designed the menu, if you have all of your content in one box then you can segment them as below, so levels with less content will not have lots of empty space. So instead of having your sections rest as vertical sections per level you could use one box, and fill each level in appropriately.