I have just returned from 2 weeks in Scotland and I received some valuable advice in these forums. I wanted to thank the posters for the good advice they regularly dispense!
We arrived September 28 and spent 3 nights at the Waldorf Astoria in Edinburgh - stunning hotel. The location is perfect, everything you could ask for from the staff and really great room. We got the king room which was HUGE. After that, we picked up a camper van from Spaceships and had it for the next 11 nights. We did not sleep in the van one time! It was a little chillier at night than we expected and I guess I'm too old/spoiled to sleep in a van these days (we did it a couple years ago in Iceland and loved it). anyway, we were able to get rooms in decent places - some better than others :-) - every night without reservations. October really seemed to be the start of the shoulder season with winter hours beginning at many castles and a lot of things were starting to close down in smaller towns. We were pleasantly surprised that things weren't overrun with tourists at all (I realize we are tourists too but I've been places that are so crowded you can't enjoy them).
We are American and driving on the left side of the road was a challenge, as were the single track, narrow roads. My suggestion is NOT to try to drive right after a trans- Atlantic flight when you are tired and just not as sharp as you will be after a little rest. We were so glad we didn't get our rental until a couple of days later. We found the people in Scotland so friendly and warm and welcoming. It was a really enjoyable trip for us.
After leaving Edinburgh our route was like this: 2 nights in Glencoe, 2 nights in Portree, 1 night in Ullapool, 1 in Inverness, 1 in Grantown on Spey, 2 in Pitlochry, back to Edinburgh for a final night before flying home.
We were so fortunate with weather - we had amazing, blue sunny skies in Glencoe and Portree! It did rain on us as we went to Ullapool and we got drenched touring the battlefield of Culloden in a sudden downpour but we really can't complain. The weather was better than expected! The only thing I can't say we loved was the full Scottish breakfast - that is not for us hahaha! Otherwise, what a beautiful country that we hope to return to! Our absolute favorite scenery was right around Glencoe and on the Isle of Skye, we also had a fantastically scenic drive from Pitlochry to Ballater and back - the scenery was rugged and wild and beautiful. If I could do anything differently it would be to linger a bit more on the western side of the country - we wanted to make sure we had time for the Cairngorms but 3 days there was likely more than we needed. I might have preferred to add that day to the area north of sky or just hang out in Glencoe a bit longer. Our best meal? The restaurant at the Portree Hotel. If ever in town, try the restaurant. It was absolutely fantastic. We also had a tremendous meal at Aspendos, a Turkish restaurant in Inverness. Those were the two best meals of the whole trip.
Thanks for your hospitality!