Did she register for baby medicines? A lot of people forget this... baby orajel, baby motrin, gas releif, boogey wipes, first aid kit, benadryl, suncreen etc. Useful items that people don't think to register for and can be put in a cute basket or something...
If you get something you love make sure you include a gift receipt in case she already has it or someone else get it too...
Gift cards are SO nice in case there is a big item they need that they don't receive (or if they maybe didn't register for them out of preference - - like a pump). Maybe get a small gift to open in conjunction with a gift card??