Awesome girlie. Should be required reading on the Wiki. No one involved in this show should be apologising for focusing storylines on Sarah. They should look at the episodes they've just produced - Earthlings, The Good Wound, Some Must Watch... and stand up and say "fuck yeah, those were ours, and they're some of our best. Deal with it." But then, you already know this :-)
FWIW, I don't think Sarah killed Winston without hesitation the first time around. There was a struggle going on with herself even then - she tried to headbutt him first before finally pulling the trigger. Second time around, it was all about John but something tells me that's not going to make it any easier for her...