"other services outside the box" not entirely sure what you mean. The pool software definitely needs to run on the same silicon.
Welp, I'm designing such a device. It won't be pretty, as they will be handmade (you can do ANYTHING with a dremel!) . I was asking about the SSD because you can get much larger HDs with a HDD, and I'm imagining these devices will just sit next to your router for years, so ideally a 10 year device will be at least 500 gigs.
The 1 TB version i built comes to ~$300 with a 750 ti, so you could get 250 h/s. And these are all retail component costs. Perhaps someday I'd be able to get scale prices somehow. Proper cooling has proven to be a pain - its difficult to find high quality small form factor fans - fans that could last 5 years of constant runtime. And then the question of how loud the fans can be.
Thanks for the clarifications, as I am just an average end-user lacking in-depth knowledge of "how it works". When I was talking about "services" I meant the merchants, whose primary task is handling transactions. If the "boxed" node is cheap, easy-to-setup and has enough power to handle thousands of transactions - I think it might receive popularity. Non-mining node can be also purchased by enthusiasts to support the network health. The key could be in comparing the yearly 24/7 electricity costs of a regular PC (or VPS subscription) VS purchase + running costs of a boxed node.
Now I see - you are trying to build the full node with mining capability. Which is a very complicated task indeed )) Keep up the good work!