Regarding the PSU. As I said I don't game anymore so one would think 1200w is overkill for general usage, and it certainly would be. However in an audio desktop setup PSU output makes a very noticeable difference in sound quality especially when your digital source goes through a USB port. You want voltage stability and no PSU produces linear output, it dips and peaks constantly. Computer components are designed to deal with that but external audio equipment doesn't have the tolerance level required for seamless high-res music reproduction. A more powerful PSU doesn't dip below an audible threshold, that's why high-end audio equipment have such massive power supplies.
About on-board WiFi. It has nothing to do with cost, it's about security. A seasoned hacker can enable it remotely even if it's turned off in BIOS, there's always twisted ways to accomplish this... even when the computer is turned off entirely, unless you remove the CMOS battery. As for Bluetooth it's a real joke, any script kiddie can enable it. Fortunately that technology is slowly fading away in favor of WiFi direct. I know this because it's happened to me to many times.
About on-board WiFi. It has nothing to do with cost, it's about security. A seasoned hacker can enable it remotely even if it's turned off in BIOS, there's always twisted ways to accomplish this... even when the computer is turned off entirely, unless you remove the CMOS battery. As for Bluetooth it's a real joke, any script kiddie can enable it. Fortunately that technology is slowly fading away in favor of WiFi direct. I know this because it's happened to me to many times.