I like that this actually gives you a sense of real meaningful distance and size. This is a sun that's still big compared to humans, and a distance to the earth that isn't negligible.
And then a real lesson about how insanely larger the solar system is when you try to get out to Jupiter and beyond.
We can always look at images or whatever if we want to get an intellectual sense of the scale of things. I think the advantage of a model is that you feel immersed in it, and I don't think you do at this scale.
It's challenging! It's hard to find a location and a scale which gives you this human sense of the sizes involved. At most scales, you have to make the planets pinpricks in size. But, especially for the inner system, you can make it work.
EDIT: Here's I think something that works.
Oh... and of course put in where Voyager, Pioneer & New Horizons probes are these days - after 40+ years of travel at ~15km/s.
The sun's radius is about 696,000 km, so 7x10^6 meters, so at 3.25 x 10^9:1 scale, it's about 2mm across. The planets would all be specks. You could see orbits, though they'd be small. And that's if you place your alpha centauri model literally "on the other side of the world" from your sol model.
This is Sweden; I would bet that there are hiking trails connecting everything on that map, although maybe not a single one for all the planets. Roslagsleden (13 day hikes) + the first 9 etapper of Vikingaleden bring you from (close to) Mars to Uranus. And these are some nice hikes:
Wikipedia has quite a list of other models [2], although it doesn't seem to include Topsfield, MA.
[1] https://www.wickedlocal.com/story/chronicle-transcript/2021/...
The Somerset Space Walk [1] seems to be a very nice candidate for your requirements.
My opinion is that this solar system model is too big to be useful. If you're trying to teach people about the scales of space, I think you need something humanly navigable, ideally something where you can see with a single sight-line back to the previous object in the model, or, failing that, where at least you can walk between elements of the model in a short enough time that you can kind of keep yourself on-task and thinking about the model for the whole walk.