Eh, altruism, self-sacrifice, kindness and such is only human as well.
That does describe human, but not (at least in my mind) "Only Human". "Only Human" (to me) implies all the frailties and flaws of the human condition. Listing it as a trouble implies negative bits of being human - especially if his high concept is linked to the divine.
Then again, I don't know what sparked the Aspect.
"When called upon to do god's work he pushed himself, time after time, hour after hour, always know that there was more that needed to be done. After falling asleep on the 43rd hour of staking out a warlock's house, he accepted that he was
Only Human, and that while god's will needed to be done he couldn't surpass his human limitations to do it." - Only Human here is about the limitation of a mortal body.
"While following a suspect warlock, a hot girl approached him and started talking to him. He answered her back and they started talking and he is
Only Human he lost sight of the warlock." - Only Human here is tied to temptation (and inspired by a scene in Dr. Horrible).
"He knew he should kill the demon, but the demon was in the body of a six year old girl who was cute as a button. True, the angel had said that the girl was already dead, that demon had possessed her dead body, but he was
Only Human and could bring himself to shoot." - Only Human here is tied to personal morality overriding divine commands.
That's the same aspect with three very different meanings.
Richard