Alternative to "old-fashioned", with a distinct and positive meaning?
Solution 1:
Old-school is often used as a descriptor with positive connotations. Some might consider it a colloquialism, but the OED has citations going back almost 200 years for even the figurative sense of the expression.
Solution 2:
Given the example above, I would suggest
'You are not old-fashioned, you have standards'
I realise it doesn't quite fit with the sentence provided, but it's complimentary and you could change it to '..you have high standards' which, given the low threshold of expectation, might be slightly humorous also.
Solution 3:
Retro or vintage perhaps? Retro seems to have a more neutral ring, whereas vintage seems to have a generally positive ring to it, but is not as close of a synonym.
Solution 4:
"You're not old-fashioned, you merely prefer the classic/standard literacy paradigm".