Hi Eladar,
Very good question. First of all, after c4, Bc5, A3 (White is preparing to play b4 to attack the Bishop), though after you played d6, white plays f3?
Here is the important question, "Why did white play f3?" this weakens the Kingside significantly... allowing Black to prevent white from castling Kingside.
Never forget: "Every pawn move is a weakening move."
and "Flat pawns, are strong pawns" (EG. pawns at f2, g2, and h2.)
Your idea of baiting white's move is a nice strategy, GMs call it "Inducing their opponent to play a weakening move."
The main question you ask is whether an early Queen move is sound, and the answer is, "Depends on the position". For example, in the French Advanced pawn variation: 1. e4 .. e6 2. d4 .. d5 3. e5 .. c5 4. Nf3 .. Qb6! The Queen's move to b6 is perfectly sound, and she is perfectly safe there for the time being. She is placing pressure on d4. 5. Be3 .. Nc6 ....
Hope this answers your question,
Cheers!
-Thomas