I would say yes. Nicotine has a bit to do with throat hit, and can even make the juice a bit "peppery" if there is a lot of it. I vape at 24mg because that's what it takes for me to stay off cigs. But I like the flavor better at 18mg nic. Oh well, one day I will go down to the 18, but for now I'm a happy camper.
Can you tell us more about the juice? Where did you get it? Is it customizable? If so, you can order it certain ways to try and reduce harshness (less PG more VG-flavor shots perhaps?).