No. Personal pictures can break Terms and Conditions (lewd, pornographic, etc.), and it takes up space on server relative to the size of the photo you uploaded.
There are many reasons why custom avatars aren't on this site, and there have been many previous threads like this shot down.
Therefore I will cite the number one reason why having armatars (these avatars) are good. Security. Restricting profile images makes for a cleaner atmosphere. I've seen numerous armatars of looping .gif breasts so, yeah yeah.
