IMO the 056 Corvette, appears to be very well armed for a vessel of its size.
I don't think the vessel has the depth to it inside to house a VLS system, and anyway, it would take up a lot of space, so something else would have to be given up. Remember you would also need room for the extra radars and electronic consoles.
As the 056 would most likely be in Chinese coastal regions, it would be protected anyway, with the help of the PLAAF, if an air attack was made from a hostile force towards the ship, the enemy fighters would be picked up long in advance, before the enemy could get in range of the Corvette.