1) first, you need to spend more on DDR4 memory to not bottleneck the iGPU to much (i.e. 2x4GB 3200MHz CL16) and make sure the memory you get is supported by the motherboard at that speed.
Newer X470 boards are more compatible with DDR4 memory but may cost more.
2) games compared:https://www.youtube.com/watch?v=mCD5JwdpKh0
Note slower memory would cause the performance to be much CLOSER due to memory (thus CPU) bottleneck.
3) VRAM is achieved by using some of system memory so if you assign 2GB (of 8GB) you have 6GB left for Windows + the game.
4) R3-2200G would leave $70 for a graphics card which isn't very much, plus I'd rather see the extra threads in the CPU of the R5-2400G
So...
My recommendation without knowing TOTAL BUDGET would be get the R5-2400G, possibly an X470 motherboard, a 2x4GB 3200MHz DDR4 CL16 memory kit (or close), then OVERCLOCK as best as possible then later on get a better graphics card.
*Make sure the CHIPSET supports overclocking. It can make quite a big difference.