Id say the one thing I kind of disagree with here is the emails. If I'm at my computer and the email says "Are you able to handle this 15 minute job for me by EOD?" I respond immediately "Yeah, I can fit that in." and then go back to whatever it was I was doing and handle it later.

If someone is asking me to do a big job I dont reply immediately and go do some prep work for the big job and email them an hour later. "Not a problem, Ill get on it ASAP."

If you respond and get tasks done immediately sometimes it makes them think you must be in the middle of something when you dont. When someone gives you a big task that will take 4 hours and they check in on you 3 hours after you reply to the email and you're almost finished, it puffs up your ability.

But in general I agree, responding to emails is a great tool for managing perceptions and expectations.