I have intensity for both the additional rage it gives as well as the 15% mana regeneration while casting.
Due to us not having a huge roster I am sometimes called on to backup heal and without intensity mana can be a problem, I assume if you are in a situation where you are never asked to help on healing you could get away without it but the extra rage is still nice.
I used to have Natural Shapeshifter but after my last respec I left four points unspent to see if I really missed it, I didn't find myself short on mana so I put three of them into Primal Tenacity which I have a love hate relationship with.
I hadn't respecced since before the patch where they lowered our shifting costs so I thought I should try it out, I have also found I have more intellect now as I am picking up more set pieces.
I should note that I don't power shift, playing with 500ms average latency poses enough of a challenge
I put the fourth one into Nature's Grasp so I only have two points in Thick Hide but even at my gear level I have enough armour.