Dont get a 42mm. A 42mm is NOT a Panerai. Resale of 42mm's is terrible, both rep and gen. I have a 6.9" wrist and 44mm is just fine (lugs don't exceed my wrist)! And if you go fo 44mm you have waaaaaay more options
I have a 17cm and I wear 44mm Panerai (e.g., PAM 111) and even some 47mm one (e.g., PAM 127, which looks great).
I have found that for me, more than the size of the case is the height. For example, the Luminor 1950 cases don't look nice (too tall) even though they are 44mm.
I would urge you to visit an AD and try some watches.