If I went to Skye not sure I would be able to stay away from Talisker! You can only hike so much and if you've see one Clan Castle you've pretty much seen 'em all! After all there can be only one...
(Actually Dunvegan Castle and Armadale Castle both sound kinda interesting!)
I know you can drive via a bridge to Skye but I wouldn't have thought Orkney was much easier than Islay. Would think you pretty much have to fly to both unless you've got a car and time to mess with a ferry.
Have a great trip!