you can mix flannels, cottons, wools, fleeces and minkie in the same quilt and make wonderful quilts! some of the best quilts out there have many mixed fibers in them- I make a lot of quilts that contain regular cottons & flannels (which are just soft cottons) homespuns, I sometimes add wool appliques, or strips of fleeces between rows of blocks...the only thing I ever consider is whether or not the fibers will launder ok together- fleece, minkie, wool, cotton, flannel all launder together nicely- I've even made quilts that contained all of the mentioned plus silks, corduroys & velvets - I was worried about the silks, but used a fusible stabilizer and they worked just fine- be adventurous! many *most* of my quilts contain flannels & regular cottons, wool batting and minkie backs- or flannel backs- what ever I decide is best at the moment.
