The basics on mine is I went through www.recroommasters.com for the cabinet and artwork and use an X arcade Tankstick for the controller. With mine the idea was more for a Mame cabinet with enough horsepower to play modern games as well, but modern stuff was mostly an afterthought. As such the tankstick isn’t really the best option for KI as the PC sees it as a keyboard, and KI gets wonky on key commands when switching to 2-player…single player works well enough though, so if you’re ok with coming up with something else for a second player, It’ll work well enough. Would probably recommend something designed for fightsticks if you’re wanting to do strictly fighting games though.
As far as having the game start up when you flip a switch…honestly I would think adding the game to the computer’s start tasks would accomplish that rather well. I personally use a front-end program for mine, though I don’t have it start up when the PC does anymore…Launch Box/Big Box is a really good front-end app…not too convoluded, pretty straight-forward in how it works…not free though, it was like $30 I think for a lifetime liscense. But you can use it on multiple systems no issue.
For the PC…I just tried to keep it simple, so it uses an Alienware Alpha R2 with an i7 processor and GTX 960 card…nothing too fancy but it gets the job done.
If you want to take a look, like Seraphs said I have a thread already here: