Okay so I've got some updates. I went to my local vapeshop today, and asked them about the VG/PG/Other ratios. Turns out the juice is 55/35/10. I will take that as 65/35, as I don't want to add anymore PG myself, I want a 70/30 VG/PG ratio, so I can finally make accurate measurements now. I ended up making a 70/30 juice with 12mg nic and 10% Capella Strawberry added. I have also added 1ml sweetener, but I don't taste the difference.
I must say, without changing my setup just yet (so still dual Ni80 24awg 8wrap measuring at .25Ohm), my flavour has improved greatly!