Most games can be installed/run without their updates (if you don't mind the nagging/delay), and some people prefer to do the updates on the WiiU itself. That's why just the game being complete is enough to count as 'ready to install'.
Although I understand why that's set up that way, I'd like to see an option to include current update / dlc as part of the criteria for categorizing in the left pane so titles with newer updates / dlc could show as partially downloaded (or some new category). An option like that seems like it would cover your case as well.