$92,000 Net revenue - $52,000 Variable expenses = $40,000 Contribution margin. This ratio is only used from the perspective of deriving the lowest possible acceptable price for a unit. In reality, a variety of other pricing concepts can be used to establish higher price points for products.
Steam OS is possibly the best, most known and used cross platform Linux gaming distribution based on  Debian Linux, it is an assortment of numerous entertainment software, you can think of it as a complete gaming platform for Linux.
What I always recommend to such an embedded systems programmer is this: Look at Embedded Linux as two parts, the embedded part and the Linux part. Let's consider the Linux part first. The Linux side. Operating systems abound and the choices are many for an embedded system, both proprietary and open source. Linux is one of these choices. No matter what you use for your development host, whether Linux or Windows or Mac, you need to learn how to program using the target OS. In this respect, using Embedded Linux is not greatly different from using VXworks, WindowCE, or another OS.