I have read 3! The Orenda, Half-Blood Blues and Annabel. I have no plans to read either The Year of the Flood, nor Cockroach (I'm with you on DeNiro's Game, and I read another of his earlier works last year and didn't like it either).
I'm normally a massive Boyden fan, but found the violence in The Orenda too graphic. I also suffered white man's (or woman's) guilt while reading...and found the whole book so incredibly sad that I actually *wouldn't* recommend it to anyone!
I loved Half-Blood Blues for it's change of perspective on a familiar story, plus I LOVE the musicality of it. I thought Annabel was a wonderful first effort.
If I had to tell all 33 million Canadians to read something for 2014, it would probably be Half-Blood Blues.
Should I read The Year of the Flood? I did read Oryx and Crake, way back when.
I think your reaction to The Orenda is precisely why Canadians should read it. We need to understand the history to understand the present-day. Boyden researched the book thoroughly and I can believe that the violence he portrayed was real. I also think the violence was necessary in order to understand the ending.
I've just started reading The Year of the Flood so I can't answer your question right now. I'll try to remember to come back when I have finished it.
I did love Half-Blood Blues but it didn't seem to have a particularly Canadian message to it. I do believe the book chosen for Canada Reads should reflect some truth about Canada and The Orenda, out of all of them, seems to do that the best.