I love the savings bond idea, but I steer clear of baby blankets as gifts. The main reason I do is that we received several beautiful ones (even personalized) for our boys that are now in the attic - I just don't know what else to do with them now that they're not babies anymore.
I would lean toward something that she will use and think of you. How about starting a charm bracelet for her - then you can add on for future milestones. I've given my nieces sterling silver bracelets and continue to give them charms for birthdays, holy communion, etc. Most of the bracelets allow you to hook the clasp to any link, so they can wear them even when their wrists are small. These are just my opinions, but I hope they help :)