Ria hits the nail on the head, there is no decent alternative.
Lass sounds just as patronising, young woman is a mouthful.
When do you become a woman without the young, 35, 30, 40???
Just woman is very hard to say in many sentences.
If people start "I saw a woman ...." I feel something negative is likely to follow
If people start "I saw a lady, girl young woman ...." I don't jump to conclusions.
But some feminists dislike lady too!
There isn't a right answer.
I'm a straight talking nonsense sort of person and unlikely to care what I'm referred too!
DD1 (14) likewise probably will never notice, she has a quiet self belief that shrugs off much of life's minor irritations.
She and I simply know what we are good at and expect to be treated as equal.
DD2 (11) is much less thick skinned.
She notices and is influenced by casual sexism.
It worries me there seems almost to be more of it now that in the 1980's