Hi, Karen,
The Braemar Highland Gathering is one of the two most famous Highland Games in Scotland, which is probably why you're having trouble finding accommodation nearby for that date. You could try looking in Ballater, or even as far east as Aboyne or Banchory if you have your heart set on attending. Aberdeen would be about a two hour drive. The nearest town south of Braemar is Blairgowrie.
Personally, I've only been to two Highland Gatherings - Echt and Luss. Both were small affairs - Echt more so than Luss. But both were highly enjoyable, and the small size meant that there was plenty of time to wander about and see just about everything. Both had the standard Highland Games events - caber toss, sheaf toss, hammer throw, tug-of-war, hill race, etc. ( Well, there are no hills near Echt, so it was a foot race!). Lots of Highland dancing competition as well.
The drive from Inverness to the Skye Bridge via Invermoriston is a good 90 minutes to two hours, traffic permitting. After you leave the A82, it's a beautiful drive. The Skye Bridge to Portree is a good hour, again depending on traffic. I don't know how much time you have to devote to Skye, but you'd need a couple of days after the day of your arrival to really do it justice. Having said that, some advance planning, and cooperation from the weather, means that you could have your day of arrival, one full day to take in some of the highlights, and half a day on your way back to the mainland.
The best way to return from Skye, especially if you're heading south to Oban, would be to take the ferry from Armadale to Mallaig, then the A830 to Fort William. The A830 is another another beautiful road, and much improved from the first time I drove it!
If you don't have time for the entire NC500, you could do a partial loop by driving from Inverness out to Lochcarron, and return by way of Glen Torridon. Or you could drive out to Gairloch, and return by way of Ledmore Junction, with a possible stop in Ullapool. Either can be done as a day trip from Inverness, given an early start, and would provide you with a good sampling of the Western Highlands.
What are your plans in Oban? Most visitors use it as a stopping off point for Mull and Iona, but if you can spare a half day, there are some good hikes on Kerrera, which is a ten minute passenger ferry trip from the nearby village of Gallenach.
You will no doubt be making many changes to your itinerary between now and September. Best wishes for your travels, and let hubby know that once you leave the Glasgow-Edinburgh area, the driving is not stressful.
Have a happy holiday season!
Mike (Auchterless)