I love a good plot, and think plot-heavy fiction gets shorter shrift than it deserves thanks to a character-centric dogma in literary tastes. (Don’t even get me started on the disrespect for setting.) Good characters without a good plot won’t necessarily make a good game, in particular.
At the same time, compelling characters are really, really important. That includes the main one; in Choicescript games, that’s generally achieved through giving compelling choices that reveal/shape the protagonist’s character. Customization choices like hair color, height, etc. are well-liked by a number of fans, but they’re no substitute for choices that reveal what the MC values. Those are the ones that make readers pause and think, and leave the longest impression.
Try to start putting those choices in as soon as you can. You don’t need to pack in the char-gen choices up front. In my own game, you pick gender and social class pretty early, but picking your name comes later, orientation even later (when the ROs start popping up), and I just put in a choice of hair length in the revised Game 2 Chapter 1, almost a million words into the story. Fill that early game space with choices that reveal character. Is your MC brave or cautious, idealistic or cynical, ruthless or softhearted? If you know the kind of choices that the story outcome will eventually hinge on – like whether the MC is willing to sacrifice their friends for their ideals, or make their robots into killing machines or autonomous hive minds, or wield a pack of lies to achieve the greater good – make sure those choices start coming in the early game.
Your voice and style will probably change as you keep writing, and even more as you keep reading. At any rate, mine certainly has. 
You’ll become more self-aware of the influences on your voice (and the possible alternatives), absorb new things you like into it, and take criticisms on board. Over time you’ll shift and grow.
I wouldn’t have been able to tell you the name of that rule, but I could have told you your use of commas was off. Most people with good grammar have absorbed the rules through extensive reading, not through memorizing a grammar algorithm with names for all the rules. Even if they can throw the name of a rule at you, that can be convenient for your initial Googling but won’t alone tell you whether it’s a “real” rule or just a preference encoded in one subset of style guides while contested by others.
I’m afraid Google work is still going to be your best bet when someone challenges your use of grammar. You can’t expect your readers to be able to cite a rule by its label, or to know the formal names of the parts of speech and verb forms that you’re arguably abusing. That’s just not how most people grasp language.