Splitting up Axe and Blunt isn't important at all. They're both top heavy swinging/chopping weapons. That means they handle mostly the same way.
Just because their weight retio is the same, doesn't mean they are used the same way. Ideally, each weapon class would have it's own skill. In medieval times, Axes were prized for their effectiveness egainst shield lines and breaking defenses, maces don't cut it that way unless they are much larger.
In the same regard, a mace fighter would not do that well picking up an axe and going at foes with it either. I just feel it's better to have weapons behave differently by which situation you would use them in, instead of how they are handled and weighted.
it would be awesome to have it back like in morrowind, Short Blade, Long blade, spear, axe and blunt.