These are the restaurants in Nairn that we were very happy with:
Bandstand Restaurant
Sun Dancer

We did not like the food at the Aurora Restaurant in Nairn.

On the Isle of Skye, we loved the Edinbane Inn, A Taste of India in Portree, The Old Inn on Loch Harport, and Fraser at Bracken Hide in Portree.

Not sure if these restaurants can seat 10 people at one table but it's worth a try. We had reservations at every one except The Old Inn where we had lunch.

I’d recommend having a car for your trip except when you are in Edinburgh. There are too many diversions along the way that you’d miss in a train. Driving in Scotland is easy and pleasant.

i agree with Janisj about Inverness. While it’s a perfectly good town, there isn’t much charm. I spent four nights there two years ago using it as a base. The city I was expecting was not the city I found. Again, it’s a perfectly good city, just depends on your taste.

Checking out all the recommended restaurants and will make reservations NOW for September!! Crazy, but I'm glad we learned to do that.
Renting car in Inverness and dropping off in Edinburgh. Staying at Sunny Brae B&B in Nairn, thanks to KarenWoo!
Staying in Ballater on the way to Edinburgh from Inverness. Haven't even thought about restaurants there yet!!
Much appreciation for all the suggestions and help.

Great to hear you are staying at Sunny Brae B&B. I hope you enjoy your stay as much as we did. Sunny Brae is beautiful, the breakfasts are delicious, and the setting is so pretty.