#3 Space for him to be the solo star
In the second half of the last century Italy had more stars than a clear summer night sky. Every year the players who'd become unforgettable icons set up their stables in the South of Europe, enjoying the sunshine and thriving in a glorious and world-class league.
The league is still world-class and the sun still shines but the stars are fewer in number. Of course, there are plenty of very recognisable names in the starting elevens of the top sides, but there is no one in the entire league that screams out at you at any given time and to anyone with a vague interest in football.
Paulo Dybala and Higuain are the biggest 'names' in the league and they aren't very big in comparison to the mammoth that is Ronaldo.
Plagued by constant comparison and having to share the limelight with Lionel Messi in Spain, Ronaldo's brilliance was often forgotten like it is for Messi. The Serie A is good for Ronaldo to have some space to be a solo star while Messi gets to do likewise.
The other top leagues are already full - Ligue 1 has Neymar and the Premier League has too much money and too many stars to care anymore, and the Bundesliga has never been a star driven league.
Italy has thrived on having big names play there, the money and interest generated can only be good for the Serie A as it is for Ronaldo.