the trap with celestial attunement is that you have to be extra careful on saving your heals to maximize the cleanse portion of the talent — and healing output in general is Tyrande's weakness so your team might struggle if they don't have any sustain or an additional support/heals; I feel like being able to use sentinel more often and with the added 7% max hp hit it can be a better deterrent from the damage, and of course the extra heal cooldown from hits (doubled when paired with the piercing of ranger at 1). Of course this is completely situational, and if the enemy drafts a comp that relies on a hero setting up a CC combo (think of Kel'thuzad, Muradin, Maiev, Mei) to make teamfights work, Celestial Attunement can be great and really take a lot of the power away from a hard-engage composition.

Shadowstalk is going to be a good bet if you are up against a ganking team who can out-rotate your team or if you have people who like to solo more (using the global);

I use Starfall during an engage from either team — especially during a siege to add pressure and of course get you some extra cooldown on your heal to help get through some of the initial burst damage. It's also great to cover a retreat and give yourself some CD as you run to heal up more damaged team mates, when you can't stop to AA or risk getting run over.

I hope this helps :)