All above suggestions are good. Some other thoughts..
Islay good for a stopover - especially if you organise a visit round one of the distilleries (most accomodate this).
Campbeltown. Formerly Machrihanish and now a civil airfield. If you fancy landing on a 10,000 ft runway without paying Heathrow rates here's your chance.
Stornoway. Well worth a visit if you fancy the additional sea crossing. Lovely town and some good pub grub.
There is also Broadford on the Isle of Skye but I'll have to pass on details - not visited there yet.