My personal preference is more form follows function. Or rather, make that comfort.
A couple of examples-
I love my 42mm Patek Nautilus. It's thin profile, comfortable bracelet and light weight makes it a perfect choice for me.
To contrast, the 42mm AP ROO (secs at 12:00) I owned briefly was thick, heavy, bulky and the bracelet was not easy to size to a reasonable fit; it was either too loose or too tight (perhaps a half link would have worked well to adjust a bit). Regardless, it weighed a ton, and always felt clumsy; I had to consciously keep from knocking it into walls, door frames etc.
For me, a 40mm Oyster case is a nice inbetween- Nicely proportioned, not too thick, easy to adjust the bracelet; very organic feeling.
Panerai is okay at 44mm, as the case is rather low profile, and the lugs help stabilize the case on the wrist.
So to summarize, the acceptable size of the watch in my case really depends on the watch itself; it has to be comfortable first and foremost. That said, I don't think a 53mm watch is going to fit well, nor very comfortaby on my 6.75 in. wrist