The ties are certainly optional but you will have to be a little more particular when adjusting the gathers behind the ties when using a rod with rings. They can look messy but are easily adjusted. Just takes a little time. Of course if you use posts and knobs the gathers will be concealed and you don't have to worry about that.
The piping is applies in the bottom seam. We always use piping as it finishes the edge so nicely. If you apply trim to the top or the face of the treatment and not in the seam you can apply it on the edge just above the piping or up on the treatment several inches. If you apply it in the seam we would still use the piping but you can certainly omit it if you prefer. It's totally up to you.