Some good points, but the navigation is customizable through the admin panel. The way I see it - you are offered the flexibility to be able to layout the navigation as you perceive is correct. Everyone's view on how to do this will differ, as it is governed by both perception and need.

Need - your site may only need a common gallery for all to post to, whereas the next site is a site for aspiring artists who each need their own gallery.

Perception - it is driven by the culture that you live see more in / frequent - This will also be different for different demographics.

Designing an intuitive interface is largely reliant by these two baseline principles

It is hard to provide a 'one size fits all' package that works for everyone 'right out of the box'.