Been giving this some thought over the weekend.
In terms of the best Squad, you can't really look past France. However, there are a couple of potential concerns. Firstly, the manager Dechamps, he is often compared to Southgate in that he takes a negative approach despite all the attacking talent and players like Rabiot continue to make the team. He does hold them back somewhat in my opinion. Secondly, and this is as much a positive as it is a negative is their a such thing as too much talent and ego's to manage? which leads to the third point which is the France are on fall out/hissy fit from it all going wrong. That said, if it clicks, they win.
Given all the talk of the heat etc, im inclined to lean towards Spain, Argentina and Brazil. Spain will keep the ball against most teams so will certainly be there or thereabouts. South Americans typically shine outside of Europe. I would not say they have the best team but the players do seem to raise their game, it always feels likes the South Americans play like their lives depend on it. Thats said, back to back winners are rare in fact Brazil last did it 1958/62.
Then i have Brazil. Now, Brazil have been poor for a long time now and i still some flaws in their squad but i do think Ancelotti could be a big factor. Conditions will suit and i just have a feeling they are going to turn up to this one.
I file Portugal with England, potential and more than capable squad but ultimately wont get over the line.
My pick: Brazil