Answer
"I understand that hi low count is based on low cards 2-6 assigned plus 1 and 10, face cards and ace are assigned -1.
"Why wouldn't there be a count of 2-7 and 9-A? The only card left out would be the 8.
"Would having more data make the count stronger? Just curious."
In fact, the simple answer is no. Counting the 7 as +1 and the 9 as -1 is the Silver Fox Count of Ralph Stricker (adapted from Koko Ito's Green Fountain count). It is slightly less powerful than Hi-Lo, mainly because its .69 Insurance Correlation is quite inferior to Hi-Lo's .76.
Don