Seems to me this would just allow attackers to guess people's passwords and thus be able to steal wallets rather easily.
I completely agree if the nonce was deterministic (not exactly a nonce at all!)
Find x, where C(x) < 0x00000000FFFF0000000000000000000000000000000000000000000000000000
(x starts from 0, and increases)
Thus x is a direct function of password. Thus as Garrett pointed out, guess a password and the algorithm will create the account, moreover: lots of average users would accidentally end up sharing the same password/account.
The idea seems fine if x was a random secret number.