The rules are (surprise!) exactly the same as in the real world.
So stop censoring yourself so much. Just write what you want to say. There are only two reasons why you shouldn't do this:
A) You wouldn't talk to people like this in real life.
B) Your own idea doesn't excite you at all. Not even a little bit.
If either of these reasons applies, please don't bother us with your post.
If you do decide to follow this principle, of course, some people will hate your posts. Because (another surprise!) they won't always like your ideas.
And here's the main point: that's okay.
You didn't publish anything completely crazy, because it's something you would actually say to another person in a professional setting. So it's just your opinion and someone else simply has a different opinion.
That's actually great, because thanks to productive discussion under your post, you'll gain a lot of visibility. It's much better than staying invisible, don't you agree? And in the end, you'll either get your point across or learn something new from others.
Either way, you'll be better off.
The worst thing you can do is publish defensive "blah blah