I would say if we could keep at least two of each preferably in Crowder, Smart, Bradley, or Brown. I can see a duo of Westbrook and Cousins being the perfect duo to really give GSW/Cavs the most trouble out of any team.
I'm not convinced GSW is invincible, since they literally gave up their bench, and are nothing but a super team full of the best shooters in the history of the NBA. But their post defenders in Varejao, Pachulia, etc, are pretty much getting up there in age, and going to eventually get injured or unable to stop the beast that is DMC.
Could we go out and get these two? These two are the perfect players next to each other. Passionate, violate, and hungry to win a championship.