Qualified Perceptions

These look much more like "people I know" than your other set
I noticed that too. They're not algorithmically farther towards the other face than the first set is - I decided that maybe a familiar face is more visible when it's against a backdrop of an unfamiliar face, whereas for the Bush set, they all look *like* Bush in addition to like someone else.

and I'm pretty sure I could guess the specific people you morphed with for at least half of them
(You know all of them, for reference. :) )

Mouth closed/mouth open is a consistent weirdness with these - both the far left and far right have that issue, which also manifests as smile/not-smile and causes (I think) more oddness around the mouth, because a half-smile is a strange expression.