Perfect, thanks. I have updated the build to reflect the change in PSU. I think PC Part Picker had hidden that PSU because of the compatibility filter and it not being aware of the ATX mounting bracket.
Would it be worthwhile adding a CPU cooler? Or is it something to worry about further down the line?
With regards to HDDs, I think I will go for the WD Red 4TB. This should give me 20TB of usable space if and when I fill the case.