Oh I totally agree with you, artist really often make faces or bodies very similar to them...
Your art REALLY look like you and it makes them deeply unique and fascinating!
Lot of my art look like me too, I mean, I have a big mouth, very round cheeks, and my nose is not 'big' but not very small too lol ... I often use my face for art like this one http://www.zerick.com/images/GothicBabe8.jpg
( well of course, I'm not as sexy as her LOL )
And lol, as for me I really have some difficulties
to do very slim character because I'm my self a kind
of stereotypical fantasy girl LOL, even more since I got a baby ... lol ... it's why my women are always very voluptuous body ... lol But I think it's interesting to show that these kind of 'babe' can also be sad, mysterious or strange ... like on this onehttp://www.zerick.com/images/DevilWoman6.jpg
Fist look, she like like a typical babe for tattoos lol, but when you look at her more than couple of seconds, you can find very interesting 'feelings' around her ... same thing for that one too ... http://www.zerick.com/images/GothicBabe11.jpg
I really love to play with stereotypical 'sexy ladies' and goth/dark/bloody/sadness things together ... it sometime give a funny/weird look like this ... http://www.zerick.com/images/GothicBabe21.jpg
^_^ btw, it's why I deeply HATE when I saw art on ebay from peoples who tried to do the same face than yours .... that make no senses at all ...