When in Bloomfield, stop at Slickers for ice cream.
+1 I forgot about ice cream. I think that ice cream is essential for a successfull bike tour.
I'm not sure about the + 40km, seems a little much for that route but many times good flat quiet roads can turn out to be much faster even if they are further. For me the distance is not as important as the things I see and do along the way.
I sure hope you get some dry weather, In early August I did a tour north to Algonquin Park and got rain every day and night. After awhile it takes the fun out of the trip.
Since you are going and returning from Kingston you can use different routes on each leg of the trip, there are always many ways to make the same trip.
I'll keep a eye out for you since I now know what your ride looks like as I live on your route east of Cobourg.