I wish I was familiar enough with miniatures games to give you an answer regarding playstyle, but my experience is fairly limited. My favourite miniature game would be FFG’s X-Wing game, though I stopped playing when they went to second edition.
If your store has the space for it, have you considered setting up a league night? GF9 has a league kit that includes an exclusive Q figure, and that might be enticing enough to the purchasers to get them coming in, and you could get a good look at the game.