[@Scarescrow] [s]I think the question is, in the long-run, how do you see Sebna contributing to the world and developing? Being a massive eraser is somewhat restrictive - can it even create with a Domain(Portfolio) like that? Moreover, players who have decided to play gods who are more of a non-sentient force rather than a truly sentient being have struggled in the past. It's difficult to give something that is simply a force much characterisation or develop complex plot-lines. You might be able to do well and enjoy the novelty for a while, but eventually you're likely to get stumped.
We had a terrific player who took up a non-sentient goddess previously, and though he did simply amazing things, he eventually realised that playing something like that really became dull after a while. With that in mind, I'd very strongly recommend you consider something more flexible in the long-term than Sebna. If you're dead-set on Sebna though and really think you can do wonders with it, that's your call.[/s]

edit: after a more detailed reading of the CS, perhaps Sebna is not quite as non-sentient as I first thought. Carry on old chap