I liked Neelix/Tuvok. One of my fave relationships on Voyager. It was like the Odd Couple. The straight man and the funny man.
As such, I loved 'Riddles'. Although, there shouldn't have been an easy reset at the end. They should have kept Tuvie like that for a few episodes. I think Tuvok and Neelix should have had a better understanding of each other by season six in the show, certainly after the events of 'Tuvix'.