I decided to re-organize thread a bit, by taking all long comments/monologues into comments, so it is easier for me to manage the thread. OP has all the links to main posts so that you don’t have to scroll thread.
Author’s introductions
@amberose hi 
Whyyyy? Just why do you do them?
Most of the author’s introductions aren’t even necessary.
First of all, the writer’s introductions break the 4th wall. The fewer distractions you have in your story, the more invested reader will be. It’s like watching a movie or reading a book - reader/viewer wants to forget about reality and get into this amazing story for some time.
Secondly, what is so important you want to tell, that is worth doing it?
That you will let the reader customize a character? Well, tell it at the customization part?
That your first chapters suck, but it will get better? If you know that they suck, why would you publish them?
That your first language isn’t English and you apologize? If you feel such guilt, maybe it’s worth finding a proofreader? Or at least run your script through grammarly.com or smthg? Don’t apologize just because you’re not perfect in something. Just do it the best that you can.
That your story used sound or contains explicit language? Make a splash! Or ask someone to do it.
If the reader will be interested in something about your story, he/she will write you a fanmail!
Customization through Avatar Creator
Why?
Don’t get me wrong, it’s great that you included customization, but … Avatar creation option is limited. It doesn’t have new hairstyles, lips etc. Get a nicely done customization template! There are so many available! Check @Dara.Amarie thread.
Low-quality backgrounds
I know how hard it is sometimes to find the perfect background.
But I see it so often, that author’s use backgrounds with such a low-quality, that when you zoom on them, they become all blurry and pixely.
What I can suggest?
Well. First of all, use better quality images. 
Second. If I need to zoom on background very closely (like above 400-500%) I upload this background part as an overlay. I’m not sure why it is like that, but when you upload images as backgrounds, Episode reset them to some standard quality or something. It doesn’t happen with overlays.
Music and sounds use
There is nothing wrong with NOT using music and sounds in your story. Maybe they aren’t needed.
But if you do. Don not overuse music. I saw a couple of times when authors put music in every scene. Music should complement the scene, not just be there. Constant music all the time is kinda distracting and annoying.
Believe me, there are a lot of readers who read stories with the sound on.
Outfit names
Not that often, but it happens, that I see outfit game in story, and choices are named like “One” or “Outfit 1”. Why I dislike it?
Let’s imagine, you have 4 or 6 or 10 choices. I’m one of those people (and the majority is just like me) who likes to try em all. But when I’m at the 4th/6th/10th option, and I sorta decide what I want to wear, I can’t remember where was the one I liked. So I suggest naming these options the way they would be recognizable like “Denim shorts” or whatever, not just “One”.
Small detail, but easily done, and makes your story a bit more appealing.
Non-talking animations used with dialogue lines
I see it in almost every story!
I get it, sometimes it is hard to find the perfect animation for the specific line.
But when you use wink animations, admire, eyeroll animations with the dialogue lines - a character says something with its mouth basically closed. I donnow about you, but it seriously buggers me. Maybe I’m just too attentive to details, but I surely know I’m not the only one.
Spot commands for background (and main) characters
Yep. It requires some attention and work.
I won’t explain why it is important, because the reason is just the same.
I will post @Dara.Amarie IG post’s screenshot that I find really helpful.
Looped animations
This is a common mistake. which can happen to anyone.
Just remember. If you use looped animation, don’t forget to add @CHARACTER starts some_idle_animation after its dialogue lines, so that when other character starts talking, the first one doesn’t stand with his mouth open.
Frozen faces
Check character faces after all animations. Sometimes they are stuck with a weird face, like after the callout or greet animations. You can always put idle_shiftweight animation after their lines.
Speechbubble positions
Maybe you don’t use them. That’s fine!
But if you started once, you either continue putting speechbubble spot everywhere, or you reset it (@speechbubble reset)
Animation before every dialogue line
This is a basis. Put animations before every dialogue line! It is a must (well, except if you use loop animations).
Use zoom
Use zoom in your stories, especially for conversations that are longer than a few phrases. Zooming on talking character will make the scene more alive and dynamic. If you are not sure how to do it well - check sitcoms or something, and pay attention to camera work. it is just the same.
Exit/enter commands vs. spot commands
I personally stopped using enters and exits commands a long time ago. Spot commands are simply better
Okay, I will explain why.
First of all, well they provide better varriety of spots O_o Simple as that.
Second thing, that is just as important, especially if you place more than 3 characters. Entering and exit commands mess with the layer your character is supposed to be on.
Once I had a problem, where I had a lot of background characters, and MC was walking down the isle. I put her on her place with a spot command, layered her, everything is cool. But when she was running from the isle and I used exit command, her layer changed, and suddenly she appeared to be behind background characters.
Spot commands rule other ones suck ^^
Art scenes
God bless Mette Peleikis, who in my opinion made this art scene thing trendy.
Don’t get me wrong - I love art scenes.
If first, they fit the story, and second - they are decently done.
What I mean by fit the story?
If you want to put art scene in your story bEcAuSe iT’s pReTtY for a couple of seconds - bad news - YOU DON’T NEED IT
Where I think it is appropriate to put art scene?
When there is some kind of intense moment, that doesn’t require a lot of animations but has quite some narration. Got it? Examples… A moment before the kiss? First dance? Someone dying in MC’s arms?
Now about the quality.
I know, I know. A lot of writers sooner or later start doing art. Nothing wrong with that.
And I get it, you made something, you want to share it. But let’s be real honest here - most of the first, and second, and maybe third art things anyone does - kinda suck (mine sucked hard as well). What’s the point of putting the art scene into the story if it looks like a drawing made by 5 yo?
