I didn't get to read through everyone's posts, but I got through about half.
One thing that stuck out that I hadn't seen mentioned is that industry tends to clump together, even without major zoning. You may not have an actively polluting industry in that area now, but that can change quickly. You'll want to check with your state environmental quality website to see if there has been any applications to build new facilities.
Crime with the abandoned homes nearby can be a real issue. And trucks (especially when they engine brake) can be incredibly noisy. These are both things that can be mitigated, though, with enough work
You had mentioned not wanting your kids to miss out on homesteading while you keep looking for the "perfect homestead." Is your intent to stay here or later move to a bigger or different property? Land values will struggle to increase with the industry nearby and selling the property later will be difficult if you ever plan to move to a different property. The current owners seem to be struggling with that themselves.
Trust your instincts. You know the situation and your wishes best.
Best of luck,