Interesting perspective although I think the question of being damned by demon grabbing you while waiting for your god or not speaks to the fundamental fairness of the system rather than to the alignment system itself. If you kept to your alignment you get your place in line.
So you are neutral good servant of Selune and demon grabs you then one of Selune's champions should try to rescue your soul from hell. Sin also would have a different meaning in polytheistic universe. What Selune and Shar would consider sins would differ. The Selunite cleric who counsels her faithful to maintain hope is adhering to the tenets of her faith and a Sharran would counsels the faithful to accept loss in the hopes that Shar will wipe the painful memories from one's mind. The Sharran 'sins' when she hopes for a better tomorrow, the Selunite when she accepts losses.
I guess I always assumed that the gods perceived your intent.
And yes WotC is inconsistent because different authors have different views of morality. The love / hate works somewhat with the Deities of Fury but what about Hoar and Severash both of whom come out be chaotic neutral?
I guess it comes down to whether you like thinking about the theologies of the different gods -- if you don't and just prefer to use real morality that's fine but I want the option to play my alignment.
