Well, there are what, 30 characters? Story mode is only 5 stages.
So, if you think of it, its long in that sense. But each "story" mode (sides being unique to each character) consists of only five stages.
But like I said, the game is much more than story mode o:. The Tower mode is gunna take ma a long time.
Reminds me of Bloody Palace mode in DMC4---> aka hell mode o.o