Definitely a good starting point. Sometimes people don't seem to understand the value of privacy when you're grieving or under emotional duress. I definitely have some extended family members who don't pick up on those social cues.
Another gift to consider: a charity gift card included with the sympathy note. Flowers are nice, but when I was greiving the death of a family member the slow fade of the roses didn't make me feel much better about death. Some people already specify charities they'd like to see receive donations in leiu of flowers, but if that information isn't provided and you'd like to still send a gift, charity gift cards are a great idea.