Full disclosure, if you want an obituary that does the Doctor Who legend justice you need to look further. Maybe at some of the blogs I follow to the left of this page. This is a selfish little post on what Sarah-Jane meant to me personally.
There are two times I feel the TARDIS has carried a perfect Doctor/Companion combination. The 2nd Doctor & Jamie and The 4th Doctor and Sarah Jane. My two favourite Doctors and my two favourite companions. Obviously I have seen much more of Sarah Jane Smith, as her stories are more accessible.
As a youngster, watching my VHS releases and reading my Target novels I had no idea about feminism. I didn't realise that Sarah Jane having a brain, a career, wit and intelligence along with a proper stint as a Companion made her unique. I just knew I liked her, a lot. These were the reasons I liked her more than most I just didn't know it.
Sarah Jane didn't need a costume to be remembered. She is remembered with such fondness because of her personality and the performance. I always think her stint on Dr Who was much longer than it actually was. She was such a big part of DW for me it's surprising to learn she was only around for a few years.
She was immensely likable. Her journalistic inquisitiveness allowed her to get herself into trouble rather than her stupidity. She didn't squeal a lot but she squealed when appropriate. I loved the ways she said 'Doctor' or 'Doc-tor....' I loved her smile and her wry grins. She was lucky enough to be companion at the beginning of Tom Baker's run. When he was at the top of his game. There's a reason the BBC released so much from that era early on. It was DW gold. The TARDIS team has never been better.
I have wondered if John Smith and Sarah Jane Smith are family. That's a nice thought. They definitely had a wonderful bond.
Having said all this I have never seen the actress in another role. To me Elisabeth Sladen and Sarah Jane are pretty much indistinguishable from each other. I don't mean this to be dismissive. Just that she was so perfect in the role.
I have never watched The Sarah Jane Adventures. They didn't seem to be for me. Maybe I will sometime in the future. For now I'm remembering her and the Fourth Doctor and her feistiness.
RIP Elisabeth Sladen, you will be missed. Thanks for all you've given us, it was some of the best.