Q+K is superior if there are lots of pawns, that they can double team a pawn and win it.
dragon vs queen+knight
I am not aware of any practical examples from Musketeer Chess play, although I have had a couple of games where the Queen alone has dueled with the Dragon and the Queen can put up considerable resistance. My gut feeling is similar to Zied's that in an ordinary pure endgame position things would be pretty even, but add a one or two other pieces to the mix then things start to favor the Dragon. There is also something to be said about the two pieces ganging up on a weak point, although while they are doing that the Dragon may be giving perpetual check or a mate (since it does not need the assistance of the king to mate) in another region by itself.
This made up position is a rather one sided example of what I was trying to say above. Black can capture the d pawn with 1,.....Nc6, but is mated after 2 De8+ Kh7 3 Df8 mate. Moving the white pawn back to f4 makes things more interesting. 1...Ne6 2 f5? Qxd4 3 Dg3 Qf4 is a winning pawn ending for black after 4 fe6 Qg3+ 5 Kg3 fe6. Instead 2 Dxd5 Qxd4 3 De7+ Kh7 4 Df5+ Kg8 5 De7+ is a draw.

Any encounters?