As requested, by Andrea's International Virtual Travel Group Meeting, I'm writing up a report for my 2019 trip to the Orkneys.
I spent a week each in the Orkneys and Shetlands on an organized tour in May 2019. It was outstanding; I could not have planned a better tour myself, and I have traveled extensively. Unfortunately, RSE tours don't visit Orkney at the present time, so I had to seek out another option. I won't mention the company, but if you're interested, PM me, and I will send you their contact info.
These islands are not really set up for massive tourism such as the Italian Cinque Terra or the Spanish islands experience these days. However, they have several excellent sites to visit, which are well-managed, most by Historic Scotland. Therefore, if you have an HS membership, you get in free to these sites, such as Skara Brae, Maeshowe, the Bishop's & Earl's Palace, and 29 other sites throughout Orkney.
I flew Edinburgh to Kirkwall, their Mainland capital city, and stayed in various BnB's & hotels--including one in a former stone church-- all excellent, which the tour company booked. The tour was structured and inclusive (no hidden costs) but not a group tour. They provided me with a travel app that included all relevant tour info (itinerary, tickets, logistical info, directions, & suggestions for extra sightseeing during your free time) - this is a great idea and I would love to see RSE tours incorporate this, particularly on MyWay Tours.
On this trip, I visited five islands: Mainland (3 days), Rousay (2 days), and Westray (2 days), with day trips to Hoy & Papa Westray, and all were equally impressive. If you do visit Papa Westray (a MUST), you can fly on the world's shortest flight, roughly 2 minutes long (it took us 1:12). The flight is listed in the Guinness Book of World Records, and you can even request a certificate showing you took this flight (at Kirkwall airport).
While in the Orkneys, I saw dramatic sea arches, castle ruins, fascinating historic sites, lots of sheep, stunning coastal scenery, several dozen species of birds, a sea stack, ancient Brochs, stone circles with hardly any visitors, friendly locals, and a few beautiful churches. Most tourist sites were not crowded at all. As far as climate, there are very few trees, the land is flat, and it's windier than Chicago, so expect it to be a bit chilly. Even in the summer (right now) the high is roughly 60 degrees, so, you'll need to dress in layers. But, it was still beautiful.
One specific highlight: I spent one day on the Isle of Hoy, and loved it! I had a rental car, which you'll need for maximum accessibility, and hiked to the Old Man of Hoy, the 450-foot sea stack on the western coast. To get there, you have to take a 35-minute ferry from the mainland, drive 45 minutes across the island, and hike an hour and a half. It is ABSOLUTELY worth it! Stunning views. You're hiking through an RSPB, so you'll see lots of birds along the way. I loved it so much I'm going back to Hoy next month for three nights. I want to see more of the island and take a different hiking path to the Old Man, this time with a private guide.
On this Orkney tour, they booked me a day trip with a private guide who took me by the Brough of Birsay; unfortunately, we visited at high tide, and it was an island (like St. Michael's Mount in Cornwall) with no way out there. On this year's trip, we're spending three days on the mainland, and we'll visit the Brough at low tide (by checking the tide schedule) and be able to walk out to the "island" and visit the ancient ruins, see nesting puffins and other seabirds, and enjoy the stunning coastal views.
I'm almost out of space, so I'll wrap up for now. The trip I took, The Complete Orkneys and Shetlands, took two weeks total, with a week in each place. If anyone is interested, I can post a trip report for the Shetlands portion of this trip as well. They're fantastic!
Hope this is helpful. Happy travels!