I was totally expecting Heston to go on a machine gun rampage taking out every last mutant in the city. He really didn't kill that many. And the leader of the family not only survived the movie but actually killed the hero and then was never seen or mentioned again. I kind of like the idea of the villain winning there but it was very odd that they didn't have Lisa kill Matthias right after or something.
shareI interpreted Neville's obsession with automatic weapons as a function of his relative inexperience with firearms (he is a military SCIENTIST, after all, not a combat pro). These weapons may seem powerful, but in the end they simply are not up to the task of doing the Family any serious damage. Also, Neville is simply not a very good shot.
Neville's final assault is preordained to end in failure, of course, since he really should not be running about at night, either trying to save the perfidous Lisa, or attempting to avenge the misguided Ritchie. He already knows where the Family has its nest; it would then be a relatively easy task to mine the building, and bring it to the ground. But then, his resolve to wipe out the Family is not really as strong as he presents it, and such a victory would be hollow, compared to curing the Family, and proving Matthias wrong; perhaps this was Neville's original intent, only for him to get sidetracked by a vendetta versus the charismatic and aggravating Matthias.
Either way the Family is doomed, as the general plan is not to help or cure them; their fate is either to succumb to the disease, or die by starvation when the last Quickie-mart finally runs out of Funyuns.
Killing Neville may be a personal victory for Matthias, but it is hollow, since there is now enough serum to assure the continuance of 'normal' humanity, at least for now. Even Lisa can be cured and innoculated, as Ritchie was. The villain of this piece wins absolutely nothing, except for a memorial of a past civilization, a scientist martyred on a cross of corporate art, whose story will shortly pass on and become legend.