Theres plenty of great domestic fights that never happened. I would have loved to have seen Hatton-Witter but thats never going to happen, im sure that hatton would have won but it wouldnt have been easy. Which great british showdowns would you have like to seen that never materialised?
Not the best but in recent times I would have loved seeing Calzaghe v Collins. Also Hatton v Witter, Nelson v Haye/Macarenelli.
Don't know about it being the "best domestic fight that never happened", but I really would have loved to have seen Michael Ayers - Billy Schwer.