I am capped 14 points into Inquis, with ~16 in Shaman and the last in Justicar (which is about 14 or 15) I use the mein that gives 50% less threat and 50% more healing through whatever it says on the tooltip (Forgot)
I use Chain, atm a 2h staff because it gives 2x the stats and +2 dps than my 2h hammer, and Reparation gives more healing. I use Doctrine of Bliss (300/400 health) when I go < 50%. I don't know what a source machine is.
I'm running what is supposed to be the best spec, I will not change it because I have looked a lot and this is the best I could find.
Those elites, no matter how hard I try, are indeed unsoloable. I have tried many times
So nothing will change that fact. I pulled 3 npc mages earlier at equal level and before I could get one to 50%, I myself was at less than 40% health and dropping quickly, I had to run away. I also tried healing a dungeon but no matter how hard I tried, eventually people started to die on the first boss, multiple times. I'd probably blame it on the game, since I've healed in other MMOs with no problems as big as that. I've heard of 'mouseover macros', but I do not wish to use them.
I may as well just keep questing and perhaps tank someday.