wow that is one heck of a trip your planning.
Here is what I would do on the way up if I had this opportunity which is a dream trip in my eyes. One day my dog and I are going to do this!
I would fish nipissing or Temagami so you can say you did it and maybe you can get into one of the famous days they are known for.
From there I would hit Abitibi straight north of Kirkland lake. My wifes grandfather used to fish this lake alot and limited out in half hour for walleye more times then not. He always warned me about the rocks on this lake though. there are 700 islands so you can imagine that you dont want to go to fast as there is rock everywhere. This same rock is why there are tons of great fishing opps for Walleye and Pike.
After Abitibi I would make your way to Hearst. If it was me though I would continue on to Longlac. Longlac area is a fishermens dream. Little pressure and tons of fish. My dad used to sell for a mill up there and they used to go fishing as part of sales meetings and they would basically catch fish after fish with a jig and minnow combo for hours at a time. It was more rare not to get a bite then it was to catch a fish on everycast/drift.
From Longlac your only about 2 hours to Lake Nipigon.
From there you have all the big lakes I would fish in Northwestern ontario. On the way back I would hit White lake provincial park for the fishing opps there. It is little known but very productive from what I have heard. Finally on the way back it would be foolish not to fish a day or two on georgian bay which could very well be the most versitile fishing lake anywhere in canada. Huge Musky/pike, great walleye and bass fishing, go deeper and find rainbows and salmon.
Man I am excited for you! I hope to see a great report when you come back
Cheers!