Have you thought about doing Branching Out (Knitty.com), since you feel the need to, well, branch out? I think you might be ready to take her on. Learn how to read the chart and you'll do great. Of course it is another scarf, but it is fun and challenging but not too hard.
(Tip of the day from me: When doing chart knitting, place a sticky note under the row you are knitting. That trick alone is what made it possible for me to be successful with lace knitting.)