as long as they can be laundered together you can use them together and flannel and cotton makes a wonderful quilt!
i have made many quilts with cottons, flannels,corduroys, wools and silks all in the same quilt, it is beautiful and used all the time. i would worry a little about your shiny stuff...it may not wash up so nice, really need to make a little something, like a placemat using the shiny stuff and other fabrics, make it, finish it, wash and dry it...then you will know if you can mix them or not