Maybe the size of the box depends on the image of the brand or of a particular line of pieces from that brand.
I might expect a big box from Panerai, Hublot or AP.
I'd love a small, functional understated but well-made leather case for JLC like the etui(?) size for say, the Reverso.
It may paint a picture of what JLC is all about for that particular line. Elegance in economy. That it doesn't need to shout to introduce itself.