CS is such a powerful damage buff that attacking outside of the debuff just feels extremely unsatisfying. I'm all for the opportunity window theme but maybe they took it a bit too far with CS. (Always been more biased towards steady-reliable dps over random burst though so eh).
Instead of Slam being a fish-for-CS button, I'd much prefer if it just applied a stacking debuff, like Sunder Armor. Which would still fit the Arms fantasy of aiming for weak spots, give more reliable output and avoid turning Arms into our second RNG dps spec, as if Fury wasn't enough for that.
That would free up CS for something else entirely, one of my favorite ideas I've once read was True Strike, a long cd attack that always ignores armor, cannot be blocked, dodged or parried and is guaranteed to crit (buffed by crit chance). So literally a melee version of Chaos Bolt, or Overpower on steroids.
If they make Titanic Might a viable and powerful talent option I'm happy enough though.