I'd like to add an eighth and ninth rule: avoid 'adjective abuse', and don't use highly uncommon words.
I tried proofreading a 20-page sci-fi story: I couldn't finish it. The wildly excessive use of adjectives made Tolkein look like a rank amateur. I had to dive for the online dictionary two times in the first 5 pages 'cos he'd used words that were utterly unfamiliar.
Now, let me be clear: I've read a book per week for over 4 decades. I've read the dictionary... TWICE. If I have to look it up, you shouldn't use it. Don't try to awe the reader with your linguistic knowledge; you'll only piss them off.
There's a difference between painting a picture and detailing every damned leaf.
I finally threw in the towel about half-way through. He'd lost my attention early on, and it was painful to continue. Don't be 'that guy' (or gal). I had NO problem understanding why the story was rejected for publishing.