The 2017 version of Arcadia ran off a raspberry pi.
For 2018, I'm looking at changing this to a laptop, probably running Ubuntu or maybe Windows (if necessary). Pros and cons below.
pros - laptops are more portable and easier to work on. No need to hook up a monitor, keyboard, etc. I have a bunch of surplus Dell D630 laptops perfect for the job. They also have more disk space and memory. Running a desktop Linux OS is also easier in terms of support than running an embedded version in those in a micro-controller (like Raspian for the Pi).
cons - laptops take up more space in the arcadia cabinet than a Pi or similar micro-controller.
For the 2018 version, we replaced the raspberry pi with a Dell laptop. The software platform is Wordpress. This provides ease of programming & a rich set of features. Limitations include the inability to run MAME from the web pages (at least not easily since this is a security feature of a web server & browser combination).