True that the original "for stock" Rigby bolt guns were sold off the shelf as working rifles but they were made to a standard which would be exceptional in today's market. Very much to the standard of the metal work of the London Best rifle being offered today (engraving and fancy wood not included).
I honestly hope that the new Rigby venture is a success and especially hope that they can produce the rising bite double.
That said, one doesn't actually need to handle a gun to notice that there are shortcomings - the poor fit of the barrel band for example. IMO, you can learn more about how a bolt rifle should be made by getting your hands on some originals. Guns which were built to the standards which were demanded by customers whom actually used them every day and perhaps even bet their lives on the function and reliability of the rifle.
With the exception of the original 425Westley, I have never heared any criticism regarding barrel length of any other classic DG bolt rifle, the 416 Rigby included.
I guess times have changed and the expectations of our guns have evolved as well. My impression is that the 416 was regarded as a good general purpose medium/heavy rifle for open ground hunting and the real dangerous situations were taken up with a heavy double (the 416 being capable of that work if the situation demanded it) whereas today, the 416 is used as an all round DG rifle and likely the most powerful rifle the modern hunting client would own.
So, maybe the new standard 416Rigby is really an evolution of the original designed to the desires of the modern day hunter and it was a mistake for some (myself included) to expect a resurrection of the original rifle.