I think it would've been better overall if Luke and Leia had been born before the confrontation on Mustafar, and if Padme was killed outright by the Force grip. I'm not sure where Lucas got the idea that this obscure "will to live" business would be better than the alternative, and I've no idea what he was trying to imply with it.
"There is something going on in time and space, and beyond time and space, which, whether we like it or not, spells duty." -Winston Churchill
"For of all sad words of tongue or pen, The saddest are these: 'It might have been!'" -John Whittier
"Apathy is death." -Kreia