The only thing "shortcoming" is this blog platform. You guys should state your limitations along with the benefits you get from upgrading. Not have people rooting through forums to find out what is what, and the fact that you guys do not have a customer support phone number blows me away.
I am designing this website for a gentleman that doesn't understand website coding, but that seems to be what you guys specialize in; people that don't know the wiser. WP should have these customizations available ESPECIALLY if you are allowing people to use their own domain in replace of your WP domain.
Maybe you could point me in the direction of a better more customizable blog platform for my next client?