I went on this lovely trip in May and I would very much recommend the Segovia and Toledo optionals. They were both excellent and the history was amazing. My favorite was Segovia: the Roman aqueduct, the narrow old cobblestone streets around the cathedral, the Alcazar castle which was so beautiful from the outside (it's the model for Disney's Sleeping Beauty castle) and so interesting inside. This optional also included a great lunch ..... good food in the upstairs room of what looked to be an old country inn. Maybe it was, maybe it wasn't, but there was plenty of wine, a wonderful dessert, and a view of those cobblestone streets. This was one of my favorite days on the trip.
I went to Toledo to see "The Burial of the Count of Orgaz" by El Greco and I'm glad I did. Each group of tourists had a few minutes to enjoy the painting; no neck-craning and elbow-poking. Great idea! As for the town of Toledo itself .... nothing special. Touristy and after the magic of Segovia a slight letdown. Still, I wouldn't have missed it.
I liked the Winery/Montserrat optional, but I always enjoy wineries ..... I'm from California! I thought the setting and gardens were lovely and I really had fun sampling the wines. I found Montserrat interesting, but very crowded. All those tour buses! But it was a warm, sunny day and being in the mountains was a nice change from the cities, there was a wedding in the cathedral, and I was touched by the long, long lines of people waiting to pay their respects to the Black Virgin. Note: on the tour you will probably not have time to do this. In reflection, I would indeed take this optional again ..... but I do rate it behind Segovia and Toledo.
I didn't take the Lake Albufera optional, but those who did rated it highly. I wish now that I had joined them!