I see what you mean. Currently though the image illustrates the first in line, not the monster carrying out an action or taking a hit.
An MMIII type engine could do that, with monsters drawn in the main window (limited to a few) but here switching monster images that way and adding these effects would either cause epilepsy for most players or severely slow down combat.
In short I didn't aim to emulate MMIII, but MMII, which was less advanced but a personal favorite. Of course I realize it can't be the same for everyone but it is a choice I made early on.