I'm following football for a long time. In a post World Cup mercato and with 3 wins in a row, there will be many changes in Real. Maybe even guys like Ronaldo and Modric will leave. Real will certainly replace them with WC players, but the CL isn't Serie A or Bundesliga, where you can replace 2-3 starters in a winning team and still win with ease. Barca still can't get over Xavi and now Iniesta is done too.
Next year's CL will be won by a team preparing to win it for a long time. Bayern, Juve, City, PSG, perhaps even United.