Hi
Orkney is a great place as is Shetland. You have probably already sussed these but make sure you sea the Neolithic site Scara Brae its superb, the little museum at Stromness is good and there are some nice wildcamping spots there. Last time we were there we went to the airport and you can get flights to the out reaching islands like North Ronaldsay where you can get off, walk around for an hour or two and the fly back all for about 30 quid. The islands look superb from the air. Not sure if your into music or not but there is a local band called The Tribe and we saw them in Kirkwall and it was one of the best nights out I had ever had. Have fun!
Barry