Attacking with pieces other than your queen is sensible sometimes, but don't use other pieces just for the sake of it.
Take advantage of your queen!.
Use your queen because:
a) Its the strongest piece, therefore she can cause the most damage
b) other than the rook, the queen is the only piece that can singlehandedly checkmate the king
Now honestly, lets think about this. For everyone following the Euro championships this should strike home. Now imagine your chess pieces as a futbol team, and your opponents as the same. Like high level futbol teams, you two are evenly matched in power, its about intelligence.
Would anyone ever play to win with their weakest players? The answer, we have seen is yes with 8-10 changes in the starting lineups for the Portuguese and the Dutch. These teams essentially played with their knights. They took their queens out of practice, and then when the game mattered and they started attacking with their queen's again, Ruud Van Nistelroy couldn't protect King Van der Saar and his lead.
The queen, in competition can dominate any other piece on the board, but if you hold it back you cannot utilize her power.
Bottom line; Be mean, attack with your queen!