Some of these are great. “Could you do” takes the burden off the other person to propose something initially, and suggests respect for their time. “I will need to leave for” begs forgiveness rather than asks permissions, and since you are communicating it, it gives others the opportunity to correct your decision. These are examples of saving everyone time while still communicating them. Being too nice can be a time waste, like saying hello and then waiting for a response before asking your question.

Some of these take away the autonomy of the other person though, and that’s shitty. “When can I expect an update?” is one of those. It would be better to express this in terms of what you need and why, like “I am reporting to X person at noon tomorrow on this, could you give me an update before then?”

Of course, whether you say “just checking in” or “when can I expect…”, if you have no good reason (micromanaging is not a good reason) for checking in then you’re just being an asshole.