Graham's framework comes very highly recommended, with Buffett recommending it again as recently as 2018. Additionally, the full framework is so exhaustive as to require several days to even peruse.
GrahamValue is therefore designed to be as faithful to Graham's framework as possible, adjusting only for bond yields and inflation. This is also based on the reasoning that including any additional material would be both superfluous and unnecessarily distracting, from that which is both essential and adequate.