Considering the results thus far with small teams pulling upsets or causing significant frustration by playing defensively with excellent organization, do you think we're going back to an era where a defensive style of play is more preferred and employed more frequently?
1) Bring players who have played together or at least are tactically compatible. Spain & Germany were flat out dominant when they won because they were comprised primarily of 1-2 teams. Look @ the disaster of a Euro team that Conte brought in 2016 - made of Juventus back line + rejects. His selection of talent was good because it was tactically compatible. There were few egos and a bunch of players who were excellent at buying into his system.
2) I'm certain some players hold back during these tournaments because of their club careers. On the other extreme you have players like Vidal who are willing to permanently f up their bodies for their country. The players with that type of patriotism are those you want to bring. Players who will do anything for their national team + have a chip on their shoulders are dangerous IMO.
3) Coach - Ventura was trash and look at how that ended up. Sometimes talent can get you far but generally international coaches stink. You need a coach who can find the perfect balance of a good system and the best players. I'm positive on Mancini for this. I think he can balance this well.