There is a difference between this Barcelona and Koeman's Barcelona, there is so much difference between the two. Xavi has really improved this squad with many talented players this time. In the time of Koeman, Barcelona looked like an average league team, nobody feared them last season but Xavi has been able to transform the team to some sort of standard to compete with Real Madrid in the league.
I think it is no need to compare the current Barcelona with Barcelona managed by Koeman. Of course, it is so much different.
The current Barcelona managed by Xavi applies the nature of Barcelona tactics, tiki-taka. While in Koeman's era, he tried to avoid tiki-taka. Koeman tried to adopt Netherland national team tactics. But it totally failed because it wasn't suitable for Barcelona players' characteristics. After Xavi replaced Koeman, Barcelona returned to its nature, the players have good motivation to play again. So, they can play more aggressively and be stronger right now.