Post authors select improvement

Hello. My website has more than 8000 active members and I always have problems when I need to assign authorship of a page or post/custom posts to a particular author.
I would like the dropdown be replaced by a “ajax” field similar to the field of Tags with autocomplete function including the option “Choose from the most used…”

I believe it would also be beneficial to reduce the loading time of the post/page editing screens!