Right, finally got everything sorted. Can actually feel a draught coming from the case now so I'm pretty happy I shouldn't have problems with some gentle overclocking and the GPU I've got planned.
I've put the Akasa white LED 120mm as an inlet opposite the mobo on the left of the case, the Sharkoon Silent Eagle 80mm on the right opposite the back of the mobo as an inlet (not that I imagine it'll do much there, but it is literally silent so I'm happy), a Scythe 120mm on the bottom as an inlet and another on the top as an exhaust.
There is an increase in noise but in the time it's taken to post this I'm pretty much used to it. I might consider a fan controller down the line but I don't think it's going to be necessary.
Some photo's - apologies for poor quality, they're phone photo's:
I can't help but think my 'dump everything in the HDD enclosure' approach to cable management leaves something to be desired but it takes me forever to do basic things and I just want to enjoy it.
I wasn't able to get a photo that shows off the effect of the white LED on the side, but it works nicely with the mesh effect.