From your posted pics, your snake has all 3 major colors found in BPs, black, yellow and brown.
No yellow is axanthic (http://www.newenglandreptile.com/ner.../axanthic.html)
No black is albino (http://www.newenglandreptile.com/ner...ic/albino.html)
Hypo (ghost): http://www.newenglandreptile.com/ner...ll-python.html
Pastel: http://www.newenglandreptile.com/ner...ll-python.html
Normal: http://www.newenglandreptile.com/ner...l-pythons.html
NERDs website is just what i had on hand.
Normals have a TON of variation, some have white bellies, some have black bellies, some have stripes, some have spots, etc.
I'm glad hes eaten for you. I'd offer him food every 5 days until he bulks up a little. The triangle look i'm talking about is his spine protruding, its easily fixed as long as he keeps eating.