Elite: Dangerous is a gorgeous game... The game's team is something like > 100 people (Frontier Dev is nearly 250 - 300 employees).

They solded more than 850k copies, but the revenue per employee is indeed much less than Prison Architect.

Here's a talk at AWS Invent 2015 about the network architecture

https://www.youtube.com/watch?v=EvJPyjmfdz0