You probably already do a quick scan of emails to look for typos and other mistakes.
Use that same time to edit out phrases that soften your points, excuse something that doesn't need to be excused, apologize when no apology is needed.
All of that being said, here's a list of the sorts of things to watch for.
You have expertise, not random thoughts. Don't downgrade it.
Don't apologize. Even worse, that's apologizing for what you haven't even said yet. Adding "I understand your point" backs up your expertise.
Double whammy in that one. "Just wanted" immediately diminishes your request to a favor. "Have time" implies lesser importance.
"I'd like to..." is a preference, while "Let's meet" is an affirmative statement. 1/2
Example for smileys: Am I actually smiling about this? Am I the type who smiles a lot? If the answer is no, delete the smiley.
I have done all of these things. I still do all of these things. I've been in tech 25 years & have no confidence issues & I STILL DO THESE THINGS.
We have to become aware and be vigilant.
"Would you mind scheduling..." or "if you don't mind, can you schedule..." becomes "Let's schedule... or let's chat."
Leave the door open for disagreement but don't make the meeting sound optional unless it really is.
But when you're NOT speculating, don't hedge. State the facts and point to the evidence or data.