My opinion:

It's structure is simple, but that doesn't preclude it from being confusing.

For example, where do you go to see a list of your volumes (virtual block storage, like EBS)? Well you click on the "Droplets" button which shows you a list of Droplets (instances).

Personally, I would've rathered that they rename "Image" to "Storage" and put both images and volumes under that.