Build 2 Rigs and split them up. Much easier to try and optimize and when you are you are still mining with the other rig. Also, then you can add more 1070s when / IF you get them.
How is that going to help splitting it up?
I do plan on building another rig of once I have expanded this to 8x 1070.
Also, always have a spare barebone rig.
What is that to consist of? everything apart from GPU's?
I can build an empty rig other than GPU for about £400