Did this trip in 1984 and it was one of the highlights of my life (we spent three days with the gorillas but other than that, same trip) - and I encourage *everyone* to do it, if they can, before you get too old to fully enjoy it.
Camera: I brought a 70-200mm zoom but also brought an doubler so I could get up to 400mm, definitely worth the extra weight carrying it in the bag.
Max, looks like you hit all the highlights - good for you
Did you camp in the crater, so that you could get on the road before sunrise?
(The best stuff we saw was just at sunrise, and we were headed back to camp for breakfast as the jeeps with the people who stayed on the crater's rim were headed out for the day
)