Prosites - Upload profile image on blog signup (and in edit profile section)

Hi There,
I'd love to add the ability for users to upload their own profile image when they sign up for a blog, and also, the ability for them to edit this in profile.php in the dashboard (or, upload one if they didn't on sign up). I feel like the gravatar thng is a little wasted on my clients, it feels like unnessecary steps to take, whereas having it all done "in-house" would be much more intuitive.

Is there a decent way I can add this functionailty to Prosites and profile.php, and also remove the existing "select avatar" section in profile.php.

Thanks