Mega menus can increase engagement and reduce bounce rate if used the right way. Plenty of commercial themes come with fancy mega menu systems. Plugins like QuadMenu can add such functionality to your existing team. It lets users create mega, tab, and carousel menus for desktop and mobile devices.
You can manage the content of your menu through a drag & drop interface. Creating columns and adding widgets are pretty straightforward too. The plugin supports vertical, horizontal, and off-canvas mega menus. The premium version lets you take advantage of social, register, and other menu options to enhance your website.