I had a thought: could Zidane’s football career actually now be the best ever? Taking playing and managing as a continuum for once, instead of the normal way of considering them to be two separate things.
Personally I’d say Cruyff is probably some way clear if you look at it like that, but who else has truly excelled at both?
That's a really good question, and I think you've already answered it in some ways - surely Cruyff and Zidane would be at the top of that particular combined tree, and by some distance. I can't think of any undisputed top 20 players (and I'd say they're both top 10) who have had similar success in management. Beckenbauer comes close maybe, although his managerial career was perhaps less impressive (though maybe not actually - Wiki informs me he won the World Cup as manager...).
I'd actually suggest that Zidane might be ahead of Cruyff too - he actually won stuff with is international side, wonderful as that Dutch side no doubt were, and his three CLs in a row arguably trumps what Cruyff achieved as a manager. I reckon I'd probably go Zidane > Cruyff > Beckenbauer, although actually I'm not sure there's that much between the three of them. True giants of the game.
Wonder who'll be the next top player to go into management? Neither Messi nor Ronaldo strike me as the type, but it would be pretty cool if they did - if they could rekindle their playing rivalry as managers now that, that would be something.