Welcome to the forum Phil.
Seems to be missing some pretty basic information and in order to be of any use you might want to add some things.
Shouldn't advice on gear selection be the very first thing, rather than connections? Sure it will depend on your budget but hell even a rich man has no business buying Monster HDMI cables, right? I would also mention how important it is to research, and make informed decisions, regardless of your budget or knowledge level. Home theater, just like automotive hobbies, takes time and patience.
There are far more important things to consider than a longer cord, or a shelf, when considering front projection. I would mention the big differences like: A projector doesnt have speakers like a TV, a projector doesnt do well in a lighted room like a TV and most folks are going to need some kind of screen. Simply put, there are several reasons I have a TV and a projector in my home theater. I would mention what to look for in a display.
You talk about speakers but in such vague terms that its not really much help. How about the basics like understanding what sensitivity and frequency response means? Also with all your talk of speakers you make no mention of sub woofers, pretty big omission even for a "basic" Home Theater article. Perhaps talk about the follies of spending money on a HTIB (the biggest rookie mistake people make) verses building a better audio system from components you took the time to research yourself. I would mention what to look for in a speaker.
You also make no serious points on the heart and soul of a home theater system; the AVR or PRE/PRO. This one piece of gear is your video processor, your audio processor, your speaker power, your video switcher and your visual interface for everything in your theater. I would take the time to add information on auto room correction and recommended universal remotes to replace that piece of crap remote that came with your AVR. I would mention what to look for in an AVR; different versions of Audyssey, wattage misconceptions and streaming services that may or may not be satisfied by a blu ray player.
Nothing says you have to go in depth but perhaps at least mention the benefits of acoustic room treatments. Specifically first reflection points and bass traps which when combined can be the single largest improvement you can make to the sound quality of your home theater. These basic treatments are not really advanced concepts but rather basic home theater concepts that most people can do themselves for very little cash outlay.
There's perhaps more you could include and still not overwhelm a rookie ready to learn, like basic display calibration tips, but I think you get the point: in order to be of any use to the common Joe Sixpack you will need to be a little more specific. Since youve picked a complex subject to write about I would recommend splitting up your article with titles and good paragraph breaks, makes each category a little easier to absorb. People love images, perhaps include some pictures of cables, connections and components to break up the text of your article. If you know of web articles that have more in-depth information, how to find the right placement for your subwoofer perhaps, then include a web link within your article so at least if folks want to take it to the next level your article will still prove useful.
Again, welcome to the forum and please share your article when its complete