itch.io

Hey Matt! Keith Dunn-Fernandez here. I don't know what I can tell you that you don't know. But I'll throw out some rando comments. Feel free to ask me specific questions if you want. About me, I'm a gamer on PC and about every console you can think of from Nintendo, PlayStation, and Xbox. I'm around your dad's age and I worked with him in the theater about 25 years ago, so there's that.
I see you've used a PS4 controller so far during development. I'd caution you to reverse that and primarily use the XBOX controller unless you're specifically building for PlayStation. Basically as a player you CAN use a PS controller with some fiddling on PC but XBOX is the go-to. The XBOX controller just has more use cases.
Stereo Mode controls are baffling right now and only make sense for keyboard. If you can find a way to use your dystopian theme to display the button pushes IN the scene that would go a long way to up the fun and production value. Maybe they're on an old CRT in an apt window sometimes, or shown on a boom box, or in a car pile-up in the head-lights and tail-lights, or traffic lights at an intersection.
Beware of anything in the foreground that blocks gameplay. The poles gotta go but you could put passed-out drunks or angry cats, or other items that are low in the frame.
Unless you devise a mechanic that allows the player to fight backward and forward at the same time keep all enemies on one side or the other. Else cheap deaths ensue.
When the camera pulls out like on the bridge I'm sure you'll add some enemies flying in to attack or introduce your boss in that space as some HUGE dystopian monster or something.
It might also be fun to change-up your base mechanics from time to time with power-ups that change the game into a two-stick shooter or 2D FPS shooting gallery at the end of a level for bonus points. You might even use that as an opportunity to introduce branching narrative depending on the bonus level outcome!
You've chosen a tried and true side-scrolling genre that has a ton of opportunity for innovation now. 
I don't know if you've played the PS2/Game Cube Capcom game Viewtiful Joe. It's one of my all-time favorite games. It's has a bit of 2.5D action and it can be tough as hell at some points but the mechanics and the music and art style might be inspirational for you. I'm not saying you need inspiration! Far from it. But it was a really unusual game in the genre. And the first time I paused the game...I laughed my ass off. *No Spoilers* If you haven't played it, PLAY IT!