I would just add to the priorities:
SSD for system drive is a big plus. Then add as much 7200rpm spinning HDD storage as you need for projects and samples.
Don't go cheap on the power supply or CPU cooler and fans. You want this rig to be as stable and long life as possible.
It really is no longer necessary to overclock your system, unless you want to post your video game frame rates on YouTube. The stock clock rates of current CPUs are quite capable of handling anything a DAW can throw at them, without the need to induce potential timing instabilities or excess heat.
Your audio interface should be a major point of your research, not an afterthought. There are plenty of excellent USB audio units available now. The lowest latency units will put you into the ~$500+ club, but there are a few excellent ~$150 interfaces available, such as the previously mentioned Focusrite.
It seems for many years now that the trend has been away from internal audio interface cards, with the exception of some specialized high end stuff. Do some more research on this topic.