We did the London/Paris
ABD a few years ago (before the itinerary change). We loved it and had amazing guides (Laura and Fransesc--two of the very, very best). It is a great trip but it is really one you could do on your own, I think. We loved having the group because my son was pretty young. He really wanted to see the Eiffel Tower and loved having a group to do it with--however, London and Paris are so accessible, the ABD is not essential.
That said, the ABD (even with the new itinerary) hits the high (tourist) points of each city. My husband and I have been to both cities many times but we wanted to take my son on the "greatest hits" and it was great not having to plan the transportation, get the tickets, or stand in line. So, it depends on what you are looking for. I know you are pretty active and this is not a very active itinerary. It's more sites and history.
I have heard Scotland is the European itinerary to do if you want something active. Let me know if you have more questions and hopefully someone who has done the revised itinerary will post, too!