This is only a specific case where it changes on every sample, but how often is this the case?

It should work in any case where the quantization noise is white (if it's not, then your circuitry needs some work) and your signal frequency range is narrow enough. In that case, a filter can reduce the quantization noise below 0.5 LSB, which means that there will be no flickering provided that you're doing the numerics right.

Of course, if you have a wide-band signal, you might be out of luck.

The problem with hysteresis is that it's a highly non-linear operation, which is usually not allowed in my applications.