I think this team does desperately need a swagger, an identity. Things like talent, cohesiveness, they breed play you might call 'tough', because they can consistently play through adversity.
We also are desperately missing an enforcer. Perkins is tough. So is Zach Randolph. Nik Pekovic is tough. But so is James Johnson, and he's buried on the Sacramento bench. Toughness isn't necessarily brutish play, it's refusing to bend to adversity. Miami is 'tough', and their best rim protector was once called 'ru-Paul' by Shaq. But they're tough because they stroll into your house with a target on their back night after night and win more games than they lose, and don't apologize for it.
Again, these things really seem like narratives that are driven by observers.
The Heat lacked mental toughness when they first came together. Then they won, and they were tough and had swagger.
Dirk was soft. Then he carried his team to a title over the Heat and that talk stopped. In retrospect, some people say Tyson Chandler brought the Mavs the toughness they needed to win.
KG was a soft guy who just trash talked a lot. Then he won a title with the Celtics and he was legit tough.
Pau Gasol was soft in Memphis, then joined the Lakers and got beaten around by the physical, tough, trash-talking Celtics. Then he helped the Lakers win a title in 2009 and was the most important player in the 2010 Finals repeat. Suddenly he wasn't soft anymore.
But then the Lakers started having trouble and losing, and Pau started to have some injuries, and just like that he was soft again.