Tony,
Though I've travelled to much of Scotland, I've never been to the west coast in mid summer, because of the wee flying beasties! We've tended to either go to the Highlands in early May, the Inner or Outer Hebrides in late September, or the east coast at any time, and because of that we've never had trouble with the midges. Having said that I believe Mark is right in that the midges aren't so bad(relatively speaking) on the Outer Hebrides in mid summer.
If I was you, I would leave the Arran, Kintyre, Islay trip for a specific golfing trip or another time and blood yourselves on either Mull, The Outer Hebrides or Skye.
Mull is beautiful! If you are there, a trip to Iona is not to be missed (and a nice quirky little course there which I've yet to play). There are a couple of wildlife tours run on the island. If you book one early in a trip, you may not see everything you are hoping for but you will know what to look for and where (we didn't see golden eagles on the tour but driving past one of the spots we had stopped at on the tour and low and behold, golden eagles. Also we drove past a spot we had been watching otters from afar only to see one just off the road, that wandered past us within about 10yards as we stood by the car!) Tobermory is a nice little town. Fantastic food at the Bellachroy in Dervaig, Calgary bay is just stunning, especially at dusk. Hopefully that's enough to wet your appetite?
The Outer Hebrides are larger and there is more to cover, but as Adam says Callanish stone circle is fantastic (and will make Chris' Lochbuie Stone Circle look a little... small
) Dun Carloway Broch is worth seeing, as is Gearannan where they have restored blackhouse, even a couple available for self catering. The one we stayed in was excellent. Head out to Uig, for a stunning stretch of white sand bay, and also where the famous Norse chess set was found. Harris Golf Club looks fun also. If you then head south to North Uist you will find a great smokery where they use peat (the salmon is delicous) and the restaurant at Langass Lodge is very good. Plenty of other stuff to mention for the Western isles, but I'll just sum up by saying... ASKERNISH!
Oh, at that time of the year, you should be able to get out to St Kilda if you are on North Uist!
We drove through Skye on our way to the Harris ferry and it was wet with low cloud so I can't really speak of the island, but its well known as an absolute beauty. Adam sounds like your man for there.
You've said you aren't a fan of whisky and you've proven it by saying you don't want to visit any breweries... rather than distillerys
And not withstanding the fact that Spas are few and far between, there is more than enough to leave that till you return to civilisation.
Hope that helps, happy to give any further pointers if required.
Cheers,
James