My first concern was that a top G may not drive the cone enough and G6th or A6th might be stronger. I chose a C based tuning over the others because the pitch better suits the keys I need most - Bb at 3rd fret, G at 7th etc. and that top G sounds out just fine where it is.
But the bottom string of the usual 8st. C6th is an A and I've not much use for it, so I put the low C on the bottom string (8) and worked the C6th up from that, giving me a top G on string 2 and a vacancy on 1. But a D fits there well and gives all I want from a "virtual" 7string tuning on 8 though 2, plus the D that's often on top of a pedal steel C6th.
So that's it, I can join in with my brass pals in their flat keys as well as having some fun in G with the dobro guys.
