It seems that the words ‘traditional’ and ‘conventional’ are too charged. I suggest using ‘old-tyme’ (pronounced ‘old time-ee’) instead of either word. It’ll always leave a smile on the face of who you are talking to and not the offense of the other words.
I find myself using "non-stupid."
OK, now figure out an easy way to tell the difference between modern, post-modern and contemporary.
auld-tyme