Depends on what you mean by “efficient use of space”, I guess.
If you are organically building onto the ship or continually lumping new tech together, you’re not going to end up with straight, clean edgesor uniform proportions. And assuming intra-ship distance matters for things like power/resource distribution, the natural shape will be spherical.
Now if the borg need to pack dozens of ships into a spaceport or something, a cube starts to make more sense…
I love Biscoff cookies, but had never had them outside of a snack on a plane either. First time I realized they sold them at stores was when my local Costco started carrying them in giant boxes, which is a little like being Sir Gallahad the Chaste, and stumbling into the castle Anthrax.
Aldi has a pretty goof knockoff version in normal size packages if you have problems with moderation 😉
But to answer your question, a long time ago, my wife and I did the “Love you”, “Love you too”, “Love you… three?” thing, and apparently got up to 5 before we decided it was silly. Many years later, “Love you five” is the normal response to “Love you”.