Add the option to change Graphics Card, while lowering the spec of another part.
You would have the option to change the Graphics Card, to something more high end, then downgrading another part. i.e. Change a GTX 660 to a GTX 660 ti, then lowering a 1TB hard drive to a 0.5TB hard drive, or something along those lines.

You can manually change storage options for now, but this feature is something I do plan to implement in the future now I have automated selection based on benchmarks for graphics cards!
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trekkie00 commented
Similarly, if the option to have no graphics card at all could be added, it would be fantastic. I know some CPUs require a discrete card, but in some cases (eg, building a computer for parents) a graphics card would never be fully used and just shuffles money away from other components.