The issue with an dual purpose track is the layout. 8th scales like bigger jumps and tear up the track. 10th scale like things a little more technical. Finding a good balance and keeping up with maintaince might be an interesting task. 8th scalers will prevail in most cases (assuming the track is big enough.
Good luck with this. It is great to see places opening instead of closing. I will do my best to come on down a visit on occation!
I have an 8th scale and 10th scale cars that would love to get some time on this track!