If you're capable of carving stone into a sturdy, smooth surface, and maybe throwing in a little decorations or aesthetics to make it look nice on a table, you can probably also do a door or a chair just as well. Splitting hairs beyond that just isn't worth it.
The design for those objects is very, very different. You don't use chairs, tables, cabinets and coffins for the same things, so even if you're making all of them by cutting wood and hammering it together (to use an arbitrary example), that doesn't mean that knowing what makes a good chair means you know what makes a good armoire.
Yeah, there's a relationship there, and the material-working processes themselves are the same (or at least very similar, in most cases); I'm just saying that there's more to it than that, because what makes a good chair a good chair (for instance) is irrespective of the material at hand in many ways and will not describe what makes a good <other item>. I'm not sure, however, that this is worth splitting hairs over, which is why I mentioned what I mentioned before, about possibly not breaking things down to the individual item except in specific circumstances (like a dwarf having a particular preference).
Regarding art, that gets more into a notion of styles, and different dwarves depicting different things in different ways, which goes far beyond practical considerations. The way you're describing things is more about differences in styles than about drawing different things; you're describing artwork that evokes different styles/emotions entirely. After all, if you felt like it, you could draw a goblin in a glorious, sympathetic manner or a dwarf in a menacing, snarling manner. It's less about knowing how to draw different objects (if you know how to draw a dwarf you'll know how to draw a goblin, assuming you know what the two look like, unless you're an artist of EXTREMELY specialized technical skill, and specialized in a really weird way), and more about knowing how to draw them to different effect.
Granted, there's some truth to what you say there anyhow, in that for vastly different things (landscapes vs. people, abstract shapes vs. historical events), you might be good at one and not at others. Of course, it's also possible to, say, draw a historical person in a really bizarre and abstract manner, too, so that only goes so far. The situation is weird with art, because damn near anything is possible, since the purpose is purely aesthetic and largely arbitrary. I'm honestly not sure how I'd handle specialization for that sort of thing.