Home Server Noob looking for advice

[Host-in-the-Shell]

Personally, I'd advise against running both a game server and media server in the same machine. Not that it's wrong or a terrible idea, just that these services tend to wrestle each other for performance and that can strangle a machine under certain circumstances or generate a lot of power consumption.

If you have the required soldering skills and you're married to Windows I'd go for the N300, otherwise I'd stick to the other minipcs or consider learning Linux to maximize hardware efficiency under the N300; since you are open to suggestions for other services to host, that tells me they're probably going to grow in number eventually, and maybe you'll need more than 8GB at some point. I'd aim for the path forward rather than the roadblock: a better CPU is great to have, but only if you are going to put it to the task. Other than the game server, which I already advise against hosting in the same machine, I don't see anything super resource intensive in that workload.

In case you go for the soldered 8GB, then Linux is a great advantage; portainer, on the other hand, I'd forgo entirely. Not only are you wasting resources, but it's a layer of abstraction on top of docker that will serve as a crutch and introduce many pitfalls and portainer specific issues.