Another independent publisher here, any advice you can provide to those new to publishing would be greatly appreciated!
As the industry is changing, It is important to stay informed.
You're absolutely right! And, as I'm sure you already know, @Art Waring
, there are two major things that may seem like small potatoes that are very important: your ISBN and the editing process.
 ISBN. Nearly ever major publisher out there offers self-publishers a free ISBN when they are creating their book slot online. That's really great if you have extremely limited funds as ISBNs can cost anywhere from $70 - $110. But what most people don't know is that not having your own ISBN means you can only distribute on that platform (or through the company) that gave you the free ISBN, and that your finished work must bear that platform's imprimatur its whole life ("XYZ Press", or "ABC Publishing"). If you get your own, you can distribute wherever you like and not have any other publisher put their name on your work.
 Editor. I have fallen victim to this myself. But the simple truth is that the author is "too close" to their work to actually "see" all of his/her spelling mistakes, word fiascos, etc. You'll end up just glossing over stuff that someone else will see popping out at them as a mistake! It is worth it, even if you don't actually pay a professional copy editor, to have someone very skilled in the language of your work to edit it for spelling (spellchecks are often unreliable as they do not catch misused words all of the time), word choice, and logical / timeline flow. You might have a character, say, that pops up again accidentally after dying off, because you moved a scene to a different part of the story, and didn't realize it.
Editor work cannot be underestimated. In one circumstance, we had just made a sale to a very large game store in Wisconsin and fulfilled their order only to find out after the order had shipped that one of the pages had a duplicate entry because I had edited something at the very last moment. I had the great embarrassing opportunity to then call the acquisition manager of that store, report our mistake, and then reassure him that the error had been fixed and new copies will arrive shortly at OUR expense. Needless to say, that mistake ate up almost all of our profits for that sale.
These are just the first two suggestions off the top of my head.