Speaker recommendation for married couple

I solve this all the time with a pair of Sonus Faber Venere 2.5's.  Beautiful to look at in Gloss White, Black or Walnut, but the best part is they sound way above their price.  I've had a lot of guys come in and listen to speakers up to twice the price and at least 80% of the time they go home with the 2.5's. Never had a disappointed customer and have never had a return...well actually twice because they traded up to the 3.0's.   We always have demos, but not looking to plug us here.  Buy them locally from a reputable dealer and then take her out for a nice dinner to show your appreciation.

I'm surprised no mention of Maggie's ? 1.7 would work well. New Kef reference but out of the budget?  Also Dynaudio's are great. Best soft dome tweeters are Dynaudio's, the tsss sounds are called sibilance Btw.. DeVore are nice too.

I've had similar discussions with my wife and my wife had similar comments to your wife's. I hope we're not talking about the same wife but since you mentioned you're in Europe, we should be OK on that count since I'm in the US.
Back to speakers. You're wife's observations lead me to draw two conclusions. She like the point source sound of the Kef's and the natural sound of the paper drivers of the Sonus with it's simple crossover. The Kef's do not sound as natural to her because of the metal cone -- never a natural sounding solution. Because of close proximity ceiling surface you will need a consistent off axis response = point source or coaxial design. Or an open baffle. Also, you need paper drivers for natural open sounding vocals, such as paper cone full-rangers.
So...
Look at paper cone coaxials like Tannoy's (go for the 12" models) or Emerald Physics open baffle. They have natural, dynamic sound and are not overly bright. The point source "open baffle" designs will have less problems with ceiling and wall reflections and a natural presentation of semi-omni directivity.
Another option -- full range paper cone based speakers with woofer support like Rethm Bhaava.

Just look around -- paper cone + point source, or 8" full-range with woofer support. 
Herman

See last two posts. We both wrote concurrently and mention low ceiling and good off axis performance -- nothing will beat point source here for off axis uniformity.