I have a small Janome with same setup, and have used both copy paper and arithmetic paper for piecing including the special Carol Doak paper. I had some of the opposite tension problem, with underside having loose stitches, which I attributed to the paper swooshing in the feed dogs.
I prefer paper with a little more 'grip' to it, less slick, and before I get going I try a couple different tension and presser foot settings until I get a good fit.