Alpha isn't tuned for balance right now, but at the current point in time, it's really hard. You need to take everything into account, though. I do agree with you somewhat, but not everything is being taken into account here. What happens if you VS a DK and are at half hp, don't have bubble or bop, and the only way to survive because your healer is CCEd is to heal yourself, so you try, but you get stunned, so if you don't die you use the charger, but wait, while your getting away, the DK grips you back and they kill you.
I'm not saying it's going to be common for us to not get heals off, it really depends on the situation, but if we have practically no mobility, as well as our only source of healing is a hard casted flash of light, we're going to get countered by almost everything. A few tweaks would most likely fix the issue like a tiny bit more mobility, but currently it's not working to well in pvp. Yeah, DR is still in place, so let's say the enemy team has to wait a few seconds but you're almost dead and they then CC your healer, what are you going to do? Hard cast flash of light right in their faces?
If we had more mobility, than hard casting flash of light wouldn't be bad, we could get away behind a pillar and heal for x amount of time, but currently we can't do that either. Our only option is to hard cast flash of light right in the enemy teams faces unless you bubble, and once that's gone it's the same thing all over again until you get to the point you were at where you had to bubble before but can't because you already used it. Again though, it really depends on the situation and the comps your vsing.
TLDR: Once they get all of our defensives (bubble/bop) we have nothing left, and our only option is to hard cast flash of light, but no team is going to allow more than one, if that, and that won't be nearly enough. Need more mobility to get away so we can heal in a dire situation, or more defensive shit so we can survive if our CDs are blown and our healer gets CCed.