That'd be about as fast as I could do something like that. All I can say about speeding things up would be to think about your work flow, and try to speed up the aspects of that process by customizing your tools, and changing the shortcuts for the processes and things you use the most to something that is simple and helps make thing faster for you. For instance, I like to use load selection a lot lately, so I gave it the shortcut ctrl+l which used to be levels, but I don't use levels that often, but I use load selection a lot, sped things up quite a bit. Tooling up your shortcuts will save you loads of time, just figure out what works for you and spend a day just customizing the workspace and everything in a way that is most efficient for you.
That picture looks nice. They look well balanced and not so wonky as usual designs. The believabilty factor that its an anime is really good.
A day's work for character designs is about standard. Some though maybe a bit faster.
One thing that may change is probably the graphic design and how its presented. Im not sure if I like the giant shadow thing, since our focus is the character and as a general shape, we want to focus on the character and those shapes only. Be more simple. You can try like a grey background, white, black, an envoriment, a color thats opposite to the character, etc.
If you don't believe me, just do a google search on character designs and look at those that are colored.