It seems now that Getting married in the USA after obtaining the K1 fiance is the option of choice, allowing the newlywed couple to stay together while waiting for the green card.

 The process , as with the K3 visa, is pretty similar to the application for the green card. It is, in the end, just a choice of location for your wedding and whether you would rather apply before getting married in the usa  so you can enjoy your new life as a married couple (yet not being able to plan a reception properly being abroad)  or whether you would prefer to get married in france , plan your wedding properly and wait before leaving to the USA.

 One thing to remember, while waiting for the Green Card (or permanent resident card) is that you will not be able to travel until you get the card, unless you have asked for an advance parole at the time of application.