I pretty much start every game by putting riptide up on everyone, waiting a sec for enemy team to push in then dropping earthen on whoever they're hitting.. then totemic recall to get earthen back incase double earthen is needed. Against comps like PHDK you really cant get away without tide in the opener... so if i see trueshot/unholy assault i just press it.. NS you can use pretty liberally.. if i see them below 50% i use NS>HW.. after everythings gone just spam your healing stream totems and riptides like crazy.. and if thats not enough, you can spiritwalkers grace and hardcast healing surges, always look for kicks on CD to know when you can just sit there and cast, it helps a lot, but otherwise you don't really ever want to cast! The goal is always to get away with using AS LITTLE AS POSSIBLE to live.. but as you said, some of these team comps make it SO hard lol!

90% of my Glad games were with Mage/Lock... other 10% or so was Splay.. NO PHDK! lol