This is all great feedback, thank you so much!
I went into this project thinking more about "what can I make" than virality or marketability, so I don't really know what the game's brand is, yet. I'll try to figure it out, going forward.
The web version is strategically under-juiced to try and keep enemy-bullet collision as performant as possible. I did plan on more juice for the PC build. FEEL is an excellent point of reference. Godot has some cool tweening functions built-in, and there's actually a great GDC talk about how to make more: Math for Game Programmers: Fast and Funky 1D Nonlinear Transformations (It should work in pretty much any engine/language, since it's just lerp() + math.)
I guess the biggest surprise was the mouse movement? If you can tell me some good titles that use mouse movement the way that you prefer, that might help with my research.
My design philosophy up until this point was to make all the different control styles games usually have work in tandem with each other. If you let go of the mouse and pick up a controller, it "just works."I hoped this would let me avoid adding too many menu options for controls, but accessibility is important. I'll see what I can do.
Actually, the way the controller currently works, after you aim, if you take your thumb off the stick, the turret "locks" in the last pressed direction, and turns with the ship. Moving the mouse overrides this with mouse-aiming. I suppose I could make the mouse lock the same way.
The problem is, though, whether you aim backwards for blasting the guys chasing you, forwards to clear a path, or sideways for circle-strafing, usually it's only about 20 seconds, tops, before you need to re-adjust your aim on-the-fly, after the midpoint of a run.
Which, I suppose, isn't an insurmountable problem. It just means I need a dedicated "one-handed mode" with re-tuned game balance.
And, then, I suppose it's only a matter of time before I'll need to do all the other accessibility options, too. Ah, well. It's a good problem to have. It means people are interested in the game finally. Guess I'll start knocking out the easier ones.
(Anybody reading this who doesn't know what I'm talking about, check out https://gameaccessibilityguidelines.com/ for a gold mine of player accessibility best-practices for game devs!)