Sassafras is one of my favorites ever since my dad used to make us sassafras tea in the spring!
One thing you should know. REAL sassafras is a carcinogen. So if the flavor concentrate has real sassafras in it, it's risky.
Beyond that, I've never tried that, but you can try just mixing it 6% with PG and
vaping, and then upping it until you find the right concentration. One thing that will often bring out flavors is vanilla, and another is (strangely enough) Jamaican Rum.