What I have found is as a healer I was trying to survive.. i.e. if some one was on me I had to get away... zero chance of standing toe to toe out healing them or killing them.. or even surviving. So the tools I used as a healer to get away I have them as dps.
What i have found is tho when you are pressuring someone they do less dps to you.. the dps of a healer is laughable, so instead of stunning and doing damage I always kept those skills up to get away.
I thought when I went dps I'd die so much more. I don't. Now when some one kills me I can go back and get some revenge... as a healer.. well.... no.