A walking foot can make a differene. For simpler seams you can align the layers before you start stitching, by placing the fabric under the foot, needle in place, they lift the fabric up, stretch it slightly. It works well on regular fabrics like cotton, and it's easy to do it as you go a long. For slippery fabrics I pin a lot, with or with out a walking foot, but I usually take out the needles before it goes under the walking foot. For regular fabrics seams shouldn't be that bad, for quilting I there's always lots of layers and no pinning, the walking foot turns out a must.