Funny you say that, my mom's skinny, but the Conners were essentially my world view, despite being an only child.
The Super Nintendo was a big out for my dad, and when we'd eat dinner with the intermingled family, it was in a kitchen very much like the one in Roseanne.
Now if you're saying she herself rang false, yeah. But John Goodman acted the hell out of that part. As to Lucy, My mom's gone in on a lot of schemes, and it's not funny like on the show, it lead to real, damaging monetary consequences, but my roommate calls them Lucy & Ethel situations.
Like when mom decided to get in on an e-shopping mall. I still use that as my primary business email, but it was 10k into a black friggin hole.