With the defensive build your goal is to not die while playing a little risky because of talents like Trauma Trigger, Advanced Block, and Clear! you are generally able, if CC is light on the other team, to get away with being middle of the pack or perhaps if you are caught out of position you have a very powerful knock back, 3 AA blocks, and a damage reduction to get you out of a bad situation.

This build is all about getting the best bang for your mana cost on Healing Beam with talents like Bioshield, Irradiate, and Couples Therapy you can keep someone with a small shield while having a burning rage effect on them all while healing yourself for 25% of the healing all while it costing 0 mana as long as the target has full hp or they are not taking enough damage to drop their shield.

With this build i recommend you try to stay as far back as you can while your Q target is close to max range since Healing Beam is pretty lenient with the hit boxes.

Stim Drone is an amazing choice if you have a strong ADC on your team such as Valla, Raynor, Illidan, Sgt. Hammer, Tychus, The Butcher or even Falstad to give them a very noticeible buff to their atk speed.

Medivac Dropship is my personal favorite since the cool down is crazy low and on any map with a boss is highly recommended since if you win a teamfight post lvl 10 you can use it and get a boss or keep or core.

I almost forgot about this level 7 talent! Cleanse is a very powerful tool in certain situations such as against a Murky or a very CC heavy comp with Muradin, Kael'thas, Tyrande, Kerrigan or Uther to help mitigate some of that CC and maybe save a life.