If he's overcome his statist nature enough to really mean that, i.e. no prosecutions of people who defend themselves and taxes reduced by the amount of the police budget, then sure, let's go for that. Municipal police forces are a relatively recent (a century or so) occurrence, and one not entirely compatible with individual freedom. That's why I think he's bluffing. If it's good for freedom, Bloomberg can't possibly be for it, or even allow it for long.
But he couldn’t actually allow that, because the good results would show him up for the petty tyrant and enemy of the people that he’s always been. OTOH, he may have drunk the statist Kool-Aid to the degree that he doesn’t actually REALIZE it would work out well.