That first percentage ratio the Bob posted is an excellent and most common percentage for cigarette blends. For pipe blends the ratios can be all over the map but thats understandable with the various ways of treating tobaccos to get the various styles. Perique, latakia, cavendish to name a few. The captian black gold is a golden cavendish using just fluecured tobacco for example.
I'm a cigarette smoker myself but like the pipe once in a while. I've tried my blend in of cigarette tobacco which is typically 60:30:10 fluecured:burley
riental in a filtered pipe just the other day and found that it was a pleasant alternative to rolling my cigs, I need to explore this further.