Your texture quality is on High, though setting it to Very High (if you can) will have little to no effect
The Team Fortress 2 characters look better for me because i use a high quality texture pack that is still in the works (i think)
I actually haven't done a pose with non-TF2 characters in quite a while, but the Team Fortress 2 characters are more photogenic (to me at least), so i'll try doing some Half Life 2 character pictures