First off, I wish to congratulate you on completing a fantastic, and fantastically difficlut, trip in excellent style. I am very impressed in every way. The photos and video are fantastic, and I would love to see a feature-length documentary.
A couple of comments on gear come to mind. I'm impressed that you got anywhere at all with 80kg of weight. I suspect that all of the gear trimming you could do would not seem that significant, but since this is BPL, here goes.
The heaviest thing you carry by far is food. I notice that you show a bunch of "cook in the bag" meals. Aside from issues of flavor I've always disliked how much packaging these involve. Carrying large volumes of trash later on is not pleasant, and if you could leave it all at home to begin with that would be better. Consider Re-packaging that sort of food into larger bags and than re-hydrating it in pot.
You used a white-gas MSR stove. This is a bit heavy in and of itself but mostly it makes a great deal of fuel to carry. It doesn't look like you had melt snow for water but still, 25 days of cooking is quite a bit of gas. This is one of the areas where an integrated system, such as an MSR Reactor, might work out to be lighter. Possibly the new Soto white gas stove combined with a heat exchanger pot might be a contender, but we don't have any info on it's efficiency yet.
Another idea would be to burn wood. It looks like you spent quite a bit of time in areas where there wasn't any fuel though. If you did spend time in places where natural fuel was plentiful than planning to build a fire might be a good fuel-saving strategy. Perhaps even carrying a small wood-burning stove as well as the other stove.
I suspect that far and away the best option of a backpack for carrying such large loads would be a custom-built Mchale "Bubble Pack." There are other options out there, including the new Kifaru packs (which might not be durable enough for this sort of trip), the Titanium Goat pack (which looks good, but I don't think has really been proven with nearly that much weight), and the Cilo Gear 75L. I suspect that a true custom-fitted suspension, with very strong stays and adequate hip-belt and shoulder-strap padding, attached to a big bag with very few features, will prove to be the best option.
As far as shelter goes. A small, but not too small, double-peaked pyramid with mosquito-netting skirt is probably the lightest reasonable possibility. A standard pyramid would be quite reasonable as well, although not quite as good in the wind. A Golite Shangri-la 2 or similar. Methinks one could be built out of .75oz cuben and weigh around a pound.
The camera gear is the big kicker. I'm not sure what can really be done to make it lighter. I suppose some MYOG experts around here could probably brew up a tripod using your trekking poles and one other poll (maybe your paddle shaft?) That is adequate for filming. I know some still photographers who consider a mono-pod adequate for serious backcountry photography. I guess the real hope is that the camera companies will continue to evolve smaller-lighter micro-four-thirds equipment so that it can serve for this sort of thing.
Once again, congratulations on an amazing trip.