Why is this thread in the What-If board?
Anyways, opinion is mixed and tends to split down along broadly factional lines (which was not the case for most of his leadership, but a lot of people were alienated by the way he acted in his last couple of years in charge). The fact that he now apparently disapproves of most of his government's achievements adds a slightly surreal gloss to things, of course.
Internally he overseen a top-down structure within the party, where everything was stage-managed and conference went ignored
Actually that was Neil Kinnock's doing.