I've always like that snake.
I have a mutt as well. Coastal/something. She is still thin at a bit over 6 feet long. A terrible eater, but when she does eat she will take a 1 pound rabbit. She will be 3 years old the summer.
I'm not sure if she'll grow more or not based on eating habits, but the mother is 10 feet long and I believe the father is 7 or 8.
I like the pattern on you snake more than my girl.
Your mutt is very pretty!