We had a wonderful time cruising the British Isles and for the most part the weather cooperated. Our 2nd time on the Crown Princess and again, she did not disappoint—beautiful ship with friendly, helpful staff and good food. If pressed, our only complaint would be the slow, seemingly unorganized process of disembarking at each port and the appearance that sometimes cruise tours were given preference over those passengers touring on their own—it didn't matter as we still managed to get to the sights before the bus loads, but it was frustrating.
We discovered the benefit of booking our own tours privately a few years ago when we went on the Baltic cruise and hired a guide in St Petersburg for 2 very full days with another couple from our ship. You can move much more quickly, take in more sights and have so much flexibility when touring in a small group and the cost is usually much less than booking with the ship. The ship keeps reminding you that if you aren't back in time it will leave without you—keep in mind these private guides you hire want to do continued business with cruise ship passengers and the last thing they would do is make you miss your ship. This time we were traveling with friends so it was very economical to book our own tours..I spent quite a bit of time reviewing Cruise Critic comments (thank you!) along with other online research and I pre-booked guides for: Cobh, Liverpool (but into Northern Wales), Belfast, Greenock, Invergordon and South Queensferry.
Guernsey: Bus #7 gave us a great scenic trip around the Island (find the bus station on the main road just to the left as you walk away from the port—you'll see all the buses lined up). The Little Chapel was pretty amazing and the Occupation Museum was well done. All buses return to the main station and the bus drivers are very helpful—if you have questions, just ask them!