Guy is turning 24 this year. Easy to forget that those close to 2000's are actually getting of age now. I sincerely hope the management are grooming him into becoming a captain and leader in the near future.
He's not a youngster anymore, not that it shows except for a few mistakes here and there. But I don't expect him to progress much more. If he shows his top level consistently he's comfortably a top 3 CB in the world.
I'm content with the level Araujo is playing. To progress further into top 3 he'll need his teammates to up their game as well. Those things go hand to hand. Southampton Van Dijk wasn't any poorer than Liverpool Van Dijk. It's the perspective of the bigger club and teammates.
Well he is fragile, he needs to be on bench against low tier opponents, especially at home. Play him away games, and stronger opponents. No need to play him against Elche, but knowing Xavi, he will play against 3rd division team in CDR.