Answer to the first question, yes, I think the design with a camera and 4 LEDs will be sh*t. It's not because I don't think you have the talent to build something great. I think there is an inherent hardware limitation. Sorry.,. I know nobody likes to be told their baby is ugly...
I'd be happy to be wrong but I'd have to see it (in person) to believe it. You aren't the first to claim accuracy of a camera gun.
The EMS Topgun 3 uses 4 LED blocks and still suffers from the same problems as all the other Camera / LED guns. I.e. You have to stand in another state for it to see the LEDs, they lag and suffer from drift (a build up of errors that causes the crosshairs to drift away from your iron sights over time).
I think these issues will be there in any system that calculates the guns position instead of detecting what it is aiming at. You can aim at any given point on-screen from a literally infinite number of angles:
As a result, current camera guns drift when you move. Arcade IR sensor guns do not. I only had to calibrate the Sega guns once for Windows. It works when I stand. It works when I sit (from left or right of the screen).
The arcade IR guns certainly require some installation but it's nothing unusual for anyone serious about this hobby. I'm not sure you could call a diy option "plug in n play" either. Whether you have 4 or 10 LED boards, there is a mounting challenge that will put some people off. My LEDs will be hidden in the bezel and invisible like on arcade cabs. To me, this makes it an issue on day one only.
If you checked it you would know the reason I did my 4 LEDs system is to address those issues specifically, because I was also not happy with the way other systems worked.
So no, my system don't have those issues.
It's based on aiming not position.
It doesn't care about the angle you aim for and has a line of sight accuracy in pretty much any angle, without needing any kind of calibration beside the first time camera sensor calibration (same as the first time calibration for arcade).
The latency of my whole system is around 5ms, faster than a real arcade system even on CRT.
The minimum distance while not being perfect, is drastically reduced compared to other IR solutions. You can stand at 1.5m from a 40inches screen, it will still work. And I'm even working to reduce it beyond that.
This of course won't ever be as good as a 10 LEDs solution obviously, and depends of the size of the screen, but it's good enough to work in most situations, for most setup, especially 2 players mode.
It's plug and play in a way that once you built the hardware and calibrated the camera, you can pretty much hotplug it on any device that supports hid mouse or joystick, and use it on any screen of any size, without any extra calibration or anything else. You can also use as many guns as you want at the same time, still without needing any extra work.
Even if it's still a diy project, it's as plug and play as it can get.
But don't just trust me on that, test it by yourself
I understand your point of view, and I respect it, but I would appreciate if you would not dismiss other people work in here without knowing what it's about.
As a community we try to improve each other work, make a solution for everyone, for every setup and need, we aren't trying to compete on who has the biggest