I have asked myself that question. Mostly, it was trying to add more capability than the corvette, because without all the extras, it offered nothing little over the smaller design except for the helo, and perhaps more range. (All at the cost of a larger crew)
This is an alternate version with more of the VLS above decks. I couldn't stick the entire installation up there, because it would have been as tall as the funnel, so there is a bit of it extending down below.
Looking at it, it's easy to see why I didn't like that setup...