How about another suggestion? How about increasing the number of permanent positions instead of low-paying temporary positions? How about job security? How about flexibility e.g. allowing women to have a couple of years off to have a kid and then reenter academia? How about improving work conditions so that working yourself to exhaustion is not considered the norm? Work conditions for scientists are basically crap. Job security is crap. Pay is crap. The only good thing about being a scientist is well the ability to do science, which is nice. But people have got to eat, kids have to be fed and clothed you know, and sometimes we might want to actually spend time with said kids and not constantly worry about begging for money or finding a new position. Basically, with the job conditions for science, you have to really really really really love science otherwise it's just an exercise in masochism. With this why would many kids choose science for a career? In the past, how many kids chose being a monk and devoting themselves to a life of sacrifice, piety, poverty, starvation and interrupted sleep as you get up in the middle of night for prayers for the sake of God? In science today there is almost a monastic attitude in which this sort of thing is *expected* as part of the norm.
Basically with the work conditions and lack of job security for young scientists today, science is not a career, it is a *calling*. Something which you have to love so much you're willing to put up with very bad work conditions and a good chance of never finding a good permanent position.
Adding more graduate students will just make things worse. More competition for jobs -> even worse work conditions and job security.