Well, truth be told, the longer a gaming company is in business, the more the ratio of a old IP/new IP is going to swing in the direction of the old. That's just the way it is, especially for a company like Nintendo that hangs on to established characters and franchises. You can only have so many releases a year and you have to retain a higher number of existing IP or you'll make your more casual users unhappy. A great many customers really don't want to learn new controls very often and would rather have something they can quickly and comfortably slip into.
Still, I think it would be good for Nintendo to have a new series every once in awhile that people associate with a particular console cycle, which is close to what we see with Sony. However, as Nintendo management decides things like that, rather than the developers themselves as with studios like Naughty Dog and Sony Santa Monica, that will probably never happen.
