I would say it's an aspect of secularism when done in a sane way.

What anyone considers sane is subjective, but if that's what you consider a more sane approach to secularism, I can't argue against that.

Well, I would say that ultimately all theocracies are that. In my view there aren't any deities, so all theocracies which claim to base their legitimacy on a supreme being are, well, wrong. They are really enforcers of cultural norms that just happen to have a belief in a particular deity as one of those norms.

Buddhism doesn't really have specific cultural norms, though, does it? As far as I know, Buddhism is based on guiding principles (wisdom, ethics, mental discipline), not on specific rules as it's the case with theistic religions. So there's not really a way for states to enforce any laws from Buddhism itself, they can only abide by its principles to make their own laws, whereas theocracies enforce laws not thought of by themselves but based on things written hundreds or thousands of years ago, often with little to no consideration about ethics, logic or usefulness.