Good point, but really I was playing with the idea of a dungeons and DRAGONS monster manual leaving out any mention of dragons! That would truly be odd!
But, yes, in addition to dragons we need at least the more basic fiends, magical beasts, fae, etc - although I disagree with them on what creatures should be considered fae, I admit (goblins, for instance). Giants and monstrous humanoids as well, of course.
Undead - as with constructs - IMHO, should be templates. You have vampiric humans, elven skeletons, dwarven ghouls, gnome ghosts, halfling mummies, etc - not just 'ghouls' or 'zombies'. Similarly, I tend to feel that while some constructs can work as creatures, many should be templates instead. But that is just my view.
As for aberrations - I tend to think there should be a few lists in the back of the MM. When an aberration is needed, the GM should roll a time or two on each list to see how many appendages it has, how it moves, what its SPAs and Su abilities are, etc. They are supposed to be aberrants, after all. Once there is enough of a creature for it to be considered a race, it is no longer aberrant IMO. Rather like joke about a thousand people wearing the same style clothes and speaking as one, saying "We are all unique individuals!" It simply is no longer the case!