James
You're not missing much with Ryburn. It's a modest 9-hole (18 tee) course, with plenty of internal OOB. It does have one of the most bizarre par 3's you'll ever play though. The drop shot par 3 10th plays (in sequence) across the 4th fairway, a small forest and the 2nd fairway to a basin green sunken behind a large mound. Once you're used to that kind of quirk then nothing else can shock you.
Ogden is definitely worth a visit, provided its dry overhead and preferably underfoot. It's one of the bleakest courses you'll ever play on a dreary day, but a delight in shirt sleeves. Sean Arble will hate the drop shot 17th, which is a candidate for the most vertiginous descent on any UK course. There are a bunch of very strategic holes out there, which clearly show Mackenzie's hand. I didn't really appreciate it so much in my youth, but it is a course worthy of study and wider appreciation.
Mackenzie completists may also want to drop into Bingley St. Ives, with its curious parkland / woodland / moorland layout and opening and closing par 3's. It was the big treat to play there when i was young, especially as it was a tour venue for 3 years in the early 80's, with Palmer, Trevino and Jacklin playing in the event.