If you don't want your character to kick the bucket, simply put, pick a safe career. Otherwise there will ALWAYS be that chance you won't be seeing another sunrise.
As novas, is there really any such thing? And, even should you choose a safe career, there are always anti-nova groups who may pick you out of a crowd simply because you've attempted to "fit in" or even hide what you are.
I'm in agreement with Mr. Fox. I believe a compromise with respect to character death would be appropriate (a percentage of their original character's experience, perhaps?), with completely new characters beginning at a decidedly lower level of experience than the average.