I would join you in the VC10 and Bristol Freighter and then, to my amazement, I struggled to find a third which I had never flown in. I haven't flown in a Viking but have done so in a Valetta which comes pretty close.
Then I thought about flying boats and would have loved to fly in one of the Empire Flying Boats so put that on top of my list.
My amazement was due to the fact that I was never much of a frequent traveller until everything was Boeing/Airbus and yet I seem to have flown in almost everything else that I would want to, and quite I few I wouldn't want to again.