That would be natural for an animated show (or at the least, the common state of things), methinks. This is why I was... wait, I now realize that I haven't specified that. What I was trying to ask you guys for opinions on was "the subjective guess for the size of the Boutique"... the emphasis on subjective. Since this is an artistic recreation, and not, say, a Scientific Modelization or an attempt at faithful rendering into a game model, what is needed is not accuracy per se, but "feel of authenticity". Ironforge in World of Warcraft is crazy large going by direct scale comparison with character models, but actually making it that large would make the place feel empty, as the entire city is designed to feel a teeny bit cramped. Grand, but cramped. Unlike places like Stormwind or Ogrimmar, going by places in the same game.
EDIT: Here's the completed boutique.
Spoiler: Where every garment is chic, unique, and magnifique
Next up, the Library Tree! Which also happens to be the most troublesome to make authentic; it isn't large by any accounts, but recreating the interior in Minecraft means that the base of the tree will have to be at least 11m in diametre, and that's going to make making the tree look realistic a considerable challenge.