spartan, I assume you're asking if it would help to add cultured gravel to your filter to help seed the biochem stars, not just to use gravel as medium in your filter. Is that correct?
If yes, that's a fine idea. Gravel or any other substance colonized with nitrifying bacteria will do the most good in the filter. That's where they'll get the richest flow of food (ammonia and nitrite) and oxygen.
After a month or two, I'd probably remove the gravel and replace it with something less likely to compact in your filter tray. Ehfisubstrat, as has been mentioned, is a good choice, as are ceramic noodles or more stars.
Good luck,
Jim