I agree, more money might contribute to more research and may or may not be a useful expenditure but I don't think it will solve the problems mentioned. It seems that limiting the number of PhD/post-doc postions such that they have a high likelyhood of ataining academic positions is the correct course. Although, I'm less familiar with the medical education system in the US/Canada it seems like this is roughly the model they follow.

We don't need industry taking advantage of the glut of PhD grads, they could be responsible for training and not take academics who quit because they can't find suitable jobs after graduation.