I stayed there recently as an Accor Diamond and had booked a Prestige Suite, which is what I got. The room was very nice, but felt a bit small (despite not being that small at 70㎡, there is a rather large powder room whose space could have been better used IMO). I initially wanted to book using SNUs, but both the Sofitel and the Fairmont were showing zero SNU availability on my dates. I picked the Sofitel out of the two kinda randomly Did a poor man's SNU by redeeming some points

I found the hotel to be nice overall. The club Millesime on the 32nd floor is really nice and I had very good food there for breakfast, afternoon tea and happy hour. There is also a rooftop bar on the same floor, but I didn't go as I could not redeem my drink vouchers there. Only the Fait Maison restaurant and the Jardin d'hiver afternoon tea place accept them. And (at least in Fait Maison) they have a different menu for the welcome drinks: most of which is tea/coffee/non alcoholic drinks, alcohol is limited to "white/red/rose wine", two cocktails and some beer.
I don't fully agree with OP's statements about the Fait Maison restaurant. While breakfast was really good - they had some baguette that is better than what I had in some hotel in France - I also had some dinner there and found the quality of the dishes to be all over the place (mind you I'm French). The MIO Japanese restaurant was better.

The hotel location is a bit far from the touristy spots, about 45-60 minutes by metro.