Michael, I think you've got the right idea with kids and the scale model race cars. Jim Honeycutt makes his own rental cars out of hard plastic r/c toy car bodies on a chassis he fabricates himself. His rental business increased substantially when he introduced these over the usual womps. He also has a custom 1/32 track (3.5" lane spacing) designed with short straights and twists and turns without getting overly challenging to drive. His raceway is in a shopping mall, and I've watched the kids come in and have fun on this track with cars they can associate with full-size ones. I've also visited 132 SLotcar Raceway in Tacoma, WA, and while this raceway has two ScaleAuto wood tracks, the emphasis is again on the scale collectibles, both 1/32 and 1/24. Once again, there were kids enjoying themselves with realistic looking scale versions of full-size cars. I've seen a few other attempts at raceways just for the scale collectibles, and they seem to come and go about the same as the usual big track raceways. However, I'm well aware there are other business factors that play a role including what I deem as outrageous rent for commercial space these days. As long as you can explore appealing to this segment of slot car enthusiasts without getting in over your head financially, I think it's a sound thing to try. If it doesn't work, there seems to be a consistent market for plastic track.
In full disclosure, I'm not part of the hard plastic slot car scene, although I do have one Fly 1/32 Panoz bacause I'm a Panoz fan. Unfortunately, the car came with a warped driveshaft, so isn't even drivable. It just sits on a shelf looking nice. I'm a metal chassis under a Lexan body guy, and I put "wing" kits on all sorts of bodies, even ones that weren't intended to have them. My thing is prototype race cars I build myself that go fast, but I appreciate and support all of the segments of the slot car hobby. Whether we run scale plastic models of full size cars, drag race, or run wing cars, we all contribute to preservation of this hobby.
I used to live near Bristol, TN, so I'm familiar with slot racing in the Carolinas in the 80's and 90's. I haven't made it to the Carolinas in a while, but look forward to being able to visit the new crop of raceways there in the not-too-distant future. Maybe we'll meet next year.