Today, we adopt a language that has been carefully constructed to avoid offensive slight, completely void of sexism, racism, etc.
Tomorrow, the language changes senses, meanings, idioms, words to accommodate the underlying prejudices/attitudes -- and so becoming the same base language we spoke before.
Do whatever you want to make a perfect language. But without a change in attitudes, people will just revert/mutate their language to accommodate their unchanged attitudes. You've got to look at the underlying issues and change those problems before the surface issue (our language) can reflect a healthier, more respectful language.
Sexism in our language has nothing to do with the words. Our language is perfectly equipped to suit those who want to avoid offending others. It's not the language that's the problem. Change the language, the sexism remains. And those people will find new ways to express it.