i have done a couple two sided quilts. one i did SID on the topside and it turned out okay. the second one i did was a quilt as you go and it was much easier. the last one i did an all over stripe patterne for the quilting so basically i did a line every couple inches which neither lined up to the front or the back squares but looked great. the hardest part is getting the front and back to stay lined up properly so i have learned to add borders to the backside so it is slightly larger than it needs to be and the excess can be trimmed off later.
i also have a hard time working a walking foot so i just stopped trying because for some reason it tends to break my needles as i'm going