CX600 is a budget power supply. Great for a replacement part in your average business PC, not something you want in a gaming machine with a high wattage processor like the FX series.
GTX960 is faster, newer, and cheaper then the majority of GTX760.
Your wireless card choice was good, but there are cheaper options. Gigabyte's little wireless AC card is impressive for its price. Connects up to my smart TV for WIDI and all kinds of things, but also supports both 2.4 and 5GHz frequencies.
Audio cards aren't really necessary for the average person. I happen to have that particular ASUS card and it is better then the average realtek audio chipset, but not significantly so. Have to spend a lot more on a sound card to really tell a difference, and then you also need the speakers, amplifiers, etc to make it worthwhile. (I have one because there was a serious issue with my microphone input on my previous motherboard)
Monitors aren't purchased often. So whenever possible try to get the best monitor you can when buying. In AMD builds I think I went with a popular 24" monitor. On this Intel build I went with a 21.5" to get it in budget, but it is also a very fast response time monitor.
Intel is a better buy when it comes to gaming performance on the average. FX 8 cores are good when you exclusively play games that support multi-threading very well, or when you have non-gaming related activities that are multithreaded (or if you like game streaming, video encoding and stuff like that) Otherwises the faster IPC on the Intel cores gets you better FPS in games.