When I make reservations I always try to pick non-peak dining times. Like an early lunch at 11:00 or a late lunch early dinner 3:00-4:00.
Expect to wait about 20-30 min outside of CRT before you make it in, even with your ressie because that place is always packed and there are many princesses to see. Also the picture with Cindy takes a little while too. But really, it's all a part of the experience and so much fun. Expect your time at CRT to take around 2 hours.
Expect to wait outside in a huge line for BOG even with your reservation but you won't be waiting out there long (the line is very deceiving). It moves fairly quickly. Also, you can pre-order your meal or order it inside so it's a pretty quick dining experience. I would say about an hour to an hour in a half if you are relaxing. You can finish much quicker if you are in a rush because the food comes our very quickly; but I wouldn't rush, it's such a beautiful place.
Tusker House was pretty quick service for my DH and I. We had the exact same reservation time which was awesome because we had the best of both worlds. We were seated immediately (as it is an odd time and not many people are there) and we had some breakfast and then lunch was served by the time we went back up. The characters came around very quickly and visited us several times. It was a fantastic experience. I think you picked a great time for that ADR.
I've never been to Biergarten so I can't weigh in.
