Not_a_boffin
Winkle Brown was probably influenced by his wartime experience of teaching pilots to land on carriers and doing carrier trials. The flexible deck was was an attempt to deal with the difficulty of precise landing and to separate landing and take off areas. It helped influence the invention of the angled flight deck.
The CVA-01 flight deck design was intended to take this further, and to reduce the difficulty for the pilot lining up. There are parallels with the design of the QEC flight deck.
orca
I suspect the extra size is for greater sea keeping - CDG had to stop operations off Libya at sea state 4. Maybe they hope to carry a squadron of ASW helicopters like other NATO carriers.
The lack of a bulbous bow in the artist's impressions is also odd. It adds buoyancy and aids launching aircraft by lifting the bow.