I do not propose to offer Owlcroft and Wright's compendium of instructions like a Strunk and White (although, to paraphrase Mark Twain, he knows everything about language usage and I know the rest). This is more of a request for my own satisfaction in reading others' posts.
First, I very much appreciate paragraph structure for ease in reading. Separating out the points being addressed helps me know the direction of argument. It also helps in searching for points I want to remember or respond to, when looking back over the post. If one is not attempting James Joyce stream-of-consciousness it would be a nice gesture to break out the ideas into paragraphs.
I don't think anyone here does this, but skipping capital letters is also unhelpful for the reader. My eye notices the capital letter that starts a sentence, so it aids my scanning.
Auto-correct and spellcheck won't prevent incorrect usage such as apostrophes where they are unneeded. In this category is the plural form of proper nouns. I think this usage question has drifted over time, but currently I think the approved form is "Clintons", not "Clinton's".
Another apostrophe issue is "it's" vs. "its". The former is a contraction for "it is". The possessive form is just like his, hers, theirs, ours---"its" is the correct form for possessive.
A confession might be appropriate here: I will sometimes edit a poster's thread title to change a clearly incorrect usage or spelling. I usually leave alone the issue of which words to capitalize in a title. The rule, I believe, is always capitalize the first word, then do not capitalize articles and prepositions, except when quoting within the title.
More in the nature of etiquette is the uncertainty of conveying irony or sarcasm. Some here suggest positively identifying such---it might make a smoothly ironic post feel clunky by adding a disclaimer, but it will help preserve comity.
That's all. I am greatly enjoying helping to support our community and its informative and entertaining discussions. Thanks to all who have shown their appreciation.