BW,
I love this route...except for the end! If I were taking 8 days to do this I would definitely spend a night on Big Crow and do the hike to the White Pines, although it is somewhat anti-climactic from what I've heard. And also a hike up behind the ranger cabin to the fire tower. While I've never done these treks since we've been focused on getting to Lavieille, they look worthwhile to me. I can't speak of the campsites on Big Crow.
The trip from taxi dropoff to Big Crow lake should take about 4 hours if you're double carrying and you could certainly do it in less, weather permitting. The trip down the Crow River from Big Crow to Lavieille will be the better part of a day...probably around 5 or 6 hours depending on water conditions. In the spring we were able to run some rapids and skip portages but I would expect that it is out of the question for July but you may be able to line a canoe down through the rocks as you're wading along some of the areas. Any deep holes are worth investigating for specs.
My favorite site on Lavieille is as you are just about to enter the big water from Crow Bay into Lavieille proper. You have to go through a short and narrow gap...the campsite on the left of this gap with the large bedrock is quite nice. Also, if the weather kicks up on any given day you would be able to get out of the site and onto some water for fishing either in Lavieille or in Crow Bay. I also enjoy the exit area of Lavieille where the Crow River heads down near Woodcock Lake. It's pretty water with a lot of structure and good flow that might hold some resilient specs.
I'd also take a couple days to explore Dickson. It's a beautiful lake and set aside an hour or so to poke around the Red Pine stand. The largest of those pines are north of the campsite by a couple hundred meters, kind of at the point around the bend...you'll see them fairly clearly when coming in from Lavieille.
As for the Dickson-Bonfield portage, I'd fake a broken ankle and get someone to carry you. It's not fun but at least you're fairly light as most of your food is gone. Go deep for the lakers with jigs, spoons or weighted rapalas. Also, there are some yellow perch in the lake which make for excellent eating as a shore lunch. Try dropping a few night crawlers around downed trees or rock faces with some cover by deep water...you never know when a spec or laker will surprise you as well!
When we go in the spring we have a 6 am water taxi and make it to Lavieille in one day, usually arriving late like 4 or 5 pm but sometimes, if the weather is bad, we'll take even longer. Lavieille is worth the effort to get to though. I can't speak of how busy it will be in that time of year but you can expect some of the more polite company as the distances you need to travel tend to keep out the "riff-raff", so to speak. When we've gone mid-week in May we can go a couple days without seeing anyone. Here's the view from the site I mentioned on Lavieille...
