I agree wholeheartedly with those who have been surprised how hard they've be hit by Lis's death. I've found myself reading the news article several times because I can't quite take it in.
Apart from the wonderful childhood memories I have of her work, I always felt that she was a highly underrated actress. She gave Sarah Jane genuine emotional depth--a considerable achievement given that the companion role was often quite limited in scope, and it's something no one else has matched.
I'm delighted that she got her own starring role in recent years, and that her own show was such a great success. I would go so far as to say that, for me personally, she was as important to Doctor Who as Tom.
"A man's work is nothing but this slow trek to rediscover, through the detours of art, those two or three great and simple images in whose presence his heart first opened."