To try and answer a few of your questions...
My plug gap was at 0.8 but had to drop it down to 0.6 because it started to miss, but others have mentioned they have also had this issue and moving to a hotter plug stopped the miss. I'm going to try this soon!
I changed both my fuel filter and upgraded my fuel pump after a few tanks... Neither showed anything abnormal, I know others that have done this as well and have seen nothing wrong. I think it might be a bit of a fallacy.