Things have been getting serious-ish with my boyfriend, and we've had some casual conversations about what to do with last names. He wants to keep his own last name for a variety of reasons, and he isn't opposed to hyphenating.

I (F) am attached to my own last name, also for a variety of reasons, both professionally (I have published work under it) and personally (my dad died when I was young, I have his last name, and I would like to carry it on). Plus I just like it!

Say our names are Josephine (fn) Rose (mn) Jones (ln) and Lucas (fn) Eugene (mn) Davies (ln). Obviously not our actual names, but I have a 6-letter 1-syllable last name w/ alliterative first and last initials, and he has a 5-letter 2-syllable last name—meaning that if we used both last names for kids, the resulting hyphenated name would not be terribly long.Both of our last names are uncommon and have never been used as given names.

It seems like, if we got married, our options would be to:

1. Hyphenate our names and our children's names, or use both without a hyphen: Josephine Rose Davies-Jones and Lucas Eugene Davies-Jones. (Our names are much easier to pronounce if his is first, and I don't really care about name order) Or Josephine Rose Davies Jones, etc., if no hyphen.
2. Take each other's last names as additional middle names: Josephine Rose Davies Jones and Lucas Eugene Jones Davies. Would allow each of us to continue using our own last names in professional contexts—I would still go by Josephine Jones and he would still go by Lucas Davies—but our full names would still contain the other person's name, which is important for both of us. Hyphenating childrens' last names, or using both names with a space, seems to make the most sense in this case.
3. Change each of our middle names to spouse's last name: Josephine Davies Jones and Lucas Jones Davies. Keeps our names shorter, and we could still hyphenate/use both names for children.

Has anyone changed their middle name to their spouse's last name, or taken their spouse's name as a middle name? I've seen plenty of feedback here on hyphenating/using both last names with a space, but less for options 2 and 3. And are there any options I'm missing here?

ETA: Smashing our names together to create the equivalent of Davnes or Jovies or something like that isn't appealing to me, and there aren't any pleasing combinations of our actual last names.

​