Wow. Thanks for the positive attitude and telling me something new.
I knew I didn't know everything about the client so this is great.

2. Thank you. I noticed that such "hidden" search field also exists in the Video Player! (of all places) So this is great.

3. Yes Correct. So if I get an email and I want to follow up or "flag" it myself as being important "to me", I would like to mark it with something. Maybe like a visible red flag or a red / pinkish background only to that email to emphasize it visually. (this would be cool actually) Then I can clear that flag/color later on.

Maybe even have an option to mark any emails with my name in the To or cc field to be shown as green or a color of my choice? (this exists in Outlook - Manage and I use it to ensure I don't miss emails which is sent specifically with my name in it and not part of some big distribution list.) This would be awesome.