Like Tosh (and I think the resemblance is deliberate, with Tina going for someone like her dad) he is a very realistic character - fine most of the time, so you forget that there have been many occasions when they've been manipulative and evil. I have met many people who are a lot of fun on a superficial level but are really dark underneath, especially behind closed doors. They're essentially confidence tricksters - you're taken in by the charm, and by their refusal to ever be wrong, but they are toxic.
I think Aunt Babe - who is dodgier on the surface but seems (by Shirley's account) to have a heart of gold beneath it - will emerge as the more genuine person. She is very like Shirley - lots of mistakes and a brittle personality, but loyal and kind.
People like Stan are forever making 'I'm just saying' remarks like the kind he made when Alfie was in the Vic. It was an attempt to wind him up which worked perfectly. If you listen to his speech, he is forever putting other people down or manipulating them.