The problem with the pi is all the customization stuff. I finally got mine setup in a case with a fan, power button, shutdown script, all the nonsense hidden, games all tested, artwork added, but it was a huge PITA that I never want to do again.
When you say "all the nonsense hidden" does this also include the "Retropie" menu? That is the deal breaker for me. What I wish you could do is boot straight to the "Arcade" game list and not be able to back out of it. But I don't think it works that way. The Retropie menu is confusing when all you have is Arcade games installed and is an easy way for guests to completely screw something up.
The image I messed around with has no boot images/text and goes straight into the list of emulators (so 1 button power on -> blank screen -> system menu) but the Retropie settings menu is still there. I wish there was a way to disable it completely but still get into it by pressing F4 or something.
Yeah, the nonsense is all that configurable stuff in the Retropie setup menus and text loading screens and booting into the most accessible list. Also, I should say, every Pi image that I've ever looked at was about 60% finished, mainly because the image creators copy each other's work and therefore each other's mistakes. It's annoying to see the same essential games, art, etc. either broken or missing in image after image.
I think you can make it as simple as a single list of arcade games with no ability to do anything but launch and exit games from the control panel, but it will take some config editing and probably messing around with scripts. Personally, I have a linux laptop to be able to manually edit the config files and gamelists, etc. within the opaque Pi folder structure. If you don't have something similar to edit linux files, you might have to access the Pi wirelessly through your PC or mess around with connecting a keyboard to the Pi (it's even difficult to use a keyboard, as the default is to use a British (IIRC) standard layout, so that several buttons will be wrong on your US keyboard until you figure out how to change that) and then struggle to navigate the Dos-esque interface that's built into the Pi.
If you can find a video tutorial that covers your exact preferred setup or a preconfigured image that looks like the 60 in 1 and you have a ton of spare time to clean out the crap, add what's missing, and simplify it even further, then maybe a Pi would be worth it. Otherwise, the 60 in 1 style board sounds like definitely the way to go. Even easier and possibly cheaper might be to get one of those mini consoles and just do a gamepad hack to interface it to arcade controls.