With regard to point 2, isn't this what newsletters are for or email notifications? I get notifications of sites I have subscribed to via email. I find it is still a very reliable and good source because my email lists are curated to suit my needs all in one place. I get payment notifications, site update notifications, and correspondences to varying lengths with people. It's pretty great, actually!
As for point 3, text images seem like a poor way to digitise text, because it makes it very unsearchable and is prone to pixelation if you are writing a lot of it. It seems like a silly solution to something that was never a problem.
Actually, I sense a hostility in your response that I sense in Twitter users often when I bring up things I don't agree with. I am not at all attacking you, but rather find the way users use Twitter interesting, because it is something I no longer do. I know every single point you have made because I was a Twitter user for about 4 years -- I deleted my account last year.
Why would I Google arguments for and against Twitter when what I am interested is in your opinion? I would hate to put words in your mouth.