Your question is difficult to understand, but I will try too.
'Nav on buttons' are often seen, and I think they are important. It allows the user to see whereabouts they are. Some navigation bars aren't too large. They perhaps have three or four items. These I would say, do not need to stand from the croud. If they do, then great, if not, I wouldn't call it a big mishap.
'Mega-menus' are now seen very frequently on the web. These contain often ten, perhaps fifteen links in them. The link within the 'dropdown' may not highlight, but the 'menu area' should so to speak.
The bottom line is that it will only add to the experience. The user will be able to tell whereabouts they are within the site's structure in seconds. If a user wishes to express to another human being where they can find some content, they will be able to express this to them in seconds. A site that does not label whereabouts within the site's structure the user is, may take a while to convey such information to someone else.