About 1st:
It was said, that separated ignores are planned, so it would be solved.
About 2nd:
a) You can turn on “do NOT recieve from strangers”
b) Who is capturing twitchs chat as it is? Most of streamers use some special clients, which (i am sure for 99%) will provide you option about displaying or not /whispers. Capturing twitch chat as it is looks same as you will stream your facebook messages and complain that some of them are too private - its MADE for being private.