For general off road use get a 32t front, and a few spare cogs for the back, but start with 16. I would avoid 1/8th unless you regulalry snap chains with your enormous strength! (Only applicable for those who are called Sir Chris Hoy) :wink:
I would avoid 1/8th setup as I and others have had problems with chains jumping off at the rear.
3/32 is fine, I’ve used it racing on a s/s, I don’t get off and generate a fair amount of force climbing (I’m 16st). I also use SRAM powerlinks so I can break the chain easily for maintenace.
Middleburn-wise I’d go for an Uno set up, otherwise I’d use a Surly 3/32 stainless ring on standard cranks.