5.9 for the average, why? Because it takes the lowest score, and Windows is ridiculously and pointlessly stupid about Hard Drive Performance. Its possible to get a 7.9, I read a thread on some forum about it once, guy ran 4 SSDs in a RAID.
As far as anything else, it would score pretty high, but really WEI is kinda useless in general. Hell, my Phenom II and 550 TI get 7.5 and 7.4 respectively. And neither my CPU or Video card are anywhere close to being on the level of those components you're asking about.