Make LoadWallet() create the KeyPool for empty wallets. Perceived startup time on first start might increase (<5s on my system, could be up to a minute on very slow hosts) as LoadWallet() is called before the UI is displayed.
This makes it safe to backup a new wallet.dat used for savings.
I like the idea, but it depends on when this is merged. If it is merged for the same release as walletcrypter, no need as it already does this in a separate thread (can be a bit slow to create + encrypt sometimes) in several places as it tries to fill the keypool every time it gets the password as there is no guarantee as to when it will next get the password.