Advice please on this cheap system

Very true. You don't even need 8gb, my PC only has 6 and I run everything just fine. An SSD would be a very nice addition to any build without one (I would put common applications on there too, like browsers and stuff, maybe OS too). If you can afford a better gpu, a GTX 970 is one of the most cost effective cards out there right now, and is more than enough to play pretty much anything. If I had $350 to get a better gpu, that's the one I would get without a doubt.