[Agemegos]

It's probably worth looking into the physics of damage, because at collison speeds above a mile per second most warheads are going to act like explosives or shaped charges, not like penetrators. They'll punch a small, slightly over-calibre hole in the face of the armour (or in the first layer of standoff armour (Whipple plating) and then spread out as they go in.

As for beams, producing widers spots for more damage is not a strategy that I've heard discussed. Rather, talk always seems to be of producing the minimum possible spot size to get the highest beam intensity and most violent interactions possible (drilling, explsive spalling) withou having beam intensities on the objective mirror that cause damamge there. I guess that once you reach a spot intensity high enough to achieve the most desireable effects you could increase spot size in line with objective size. I'm just not sure that that's fruitful if the mechanism of damage is to induce explosive evaporation of the target.