I love bib short cuz I can wear them in the summer and my love handles are hidden!!
Cycling apparel is very tough to buy for women. The jacket is a terrific idea and is probably more "returnable." More ideas are gloves, saddle bag, tools, tube, headband, sunglasses, etc.
Then another idea, years ago my hubby gave me a giant box for Xmas. Inside was another box, and then another box, etc. Finally, a little jewelry box with a gem of a Campagnolo seatpost bolt. Of course, then I knew that there was something to go with it. Give her a tube and a gift certificate for clothing. She'll figure it out.