Yeah, I've figured size was always the major difference.
I remember something about industrial replicators being used to make the fake "idyllic environment" of Risa viable - are the replicators used to somehow alter the terrain (IE, replicate millions of tons of sand to replace eroding coastlines? other, more impressive feats of geoengineering), or for more mundane, usual purposes? Given the context, I would hazard a guess at the former, which could should some light on the capabilities of industrial units.
I'd figure they're Kind Of A Big Deal, at any rate. Two industrial replicators were apparently enough to cover most of Bajor's rebuilding.