Don't be afraid of using your photo on your Twitter profile. The first few years I was on Twitter I was afraid to. I had an icon. I started reading that Twitter profiles with photos worked better. One day I debated it in my head, then on Twitter and a great tweeter told me I would get more followers if I did. It's been about 2 months and he was right - I gained a lot more followers.
They say "A Picture is Worth a Thousand Words" . So don't be shy and have your photo on your Twitter profile and see if it increases your following and interactions there. I'd love to know your thoughts of where and when you do not use your photo on social profiles.