We drove down the Champs-Élysées at around 6am, just days before or just after Christmas about 10 years ago.
It was magical with all the festive lights and decorations and brightly coloured cabins…
and the shops and buildings too.
We crawled along the length of it… enjoying every moment, finally meeting up with the others before setting off on our “exploration of hidden Paris”. We had special permission to (gently) drive in the pedestrian areas as well as normal roads and it was a wonderful experience.
The pedestrians seemed to enjoy it, as well…
EDIT: I think it’s a lovely idea to increase the parklands etc etc… I’d love to stroll down the C-E with an independent air…
Oh… I feel a song coming on…
I’ve walked it from the Arc de Triomphe to the tower and it’s a magical Avenue…
Now you’ve got me started… oh yes… the Arc de Triomphe… what a marvellous view from the top (while OH cowered with his feet firmly on the pavement).
We visited that and other wonderful monuments in Paris over the years (parking on the outskirts and taking the metro). Our daughter and her friends have had us running ragged to see everything we could in the time allowed… 
but I’ve never strolled up the C-E… although I think we cut across it once or twice…
Being on the CE for the final stage of the Tour de France is great as in general the crowds are happy and polite (not like mountain stages!). I do sometimes miss living in Paris for the buzz.
Hopefully the revamp will include some heavy duty security measures now amongst the grass and flowers.