I'm getting married soon and won't be taking my husband's name. Initially, I thought (like you), that it would be the nice thing to do, to show we were a family. I'd call myself a feminist, but I don't see it as a feminist issue - I just rather looked forward to the idea of having the same name as my husband.
However, I've now just started out in what I hope will be my career, and people know me by my maiden name. I've realized from my own experiences that it is *very* hard to trace someone who's changed name. You don't need to be a hard-nosed careerist to suffer from the fall-out.
So, what I will do is to keep my own name for work (so if I have a paper published, it will be under my maiden name). But I will be 'Mrs Husbands'Name' in everyday life. Perhaps your wife-to-be would consider something like that?
Apparently, this was the old French practice, still at use in places like Egypt where there was once a French presence. So, a woman who is born Elizabeth Smith will always be Elizabeth Smith. But if she marries Mr Jones, when she is called by her married title, she is Mrs Jones.