I will be the first to admit that I hated huttball leveling up and when I first hit 50. For all the reason you have listed. I to play a scoundrel sawbones. I get so annoyed getting knocked off platforms getting pulled into hazards.
That is when I started adapting my game. One advantage that huttball gives to you as a sawbones healer, is the ability to not be in the middle of things. The moment you get into the middle of the action, the minute you are doomed to qq.
Here is what i mean. Middle is by far the most important part of the arena strategy wise. Which has been said numerous times. Standing in the middle is a terrible idea.
When in the middle I like to stand under the ramp and heal. It provides me all kinds of protection from all sides and when ppl do come I can start kiting really easy with all kinds of corners to run around.
When I am not in the middle i am usually away from the action. I will get down into the pit or above everyone and heal from a distance.. Thus not getting knocked off. If our ball carrier does I can quickly position myself to get the ball when I am above.
If your healing as sawbones and you don't have +defensive screen and kolto cloud, because you think they are bad, then my guess is you have no idea how to use either one. ability to pop dodge while hots are hitting you followed or sometimes stacked with defensive screen is enough to usually grab the ball run to the pit through the bottom get everyone on you and toss it back up so someone can have a clean easy score.
For those 15-30sec i can become virtually unkillable. If you have another healer in the group you shouldnt die.
I have some of my best healing scores in huttball. Not that really matters because numbers for healing don't really mean much. If you are a real healer you know what I mean.