Marfitalu: An approximate value that I always liked to use was 9 for the queen 8.25 for the Marshall 7 for the Cardinal 5 for the Rook 3.25 for the bishop and 2.75 for a Knight. These weren't mathematically calculated values, but just what I felt from the 20 odd games I played on the mindsports site when they ran their cyber world championship events. Also in Grand Chess you might keep in mind that the above values might be modified somewhat since the pawns might be worth a little more in that game since they can queen faster. Maybe a premium of 1.15.

Another thing to keep in mind is that the nimble Cardinal probably outshines the Marshall at the beginning of this game, even though the latter is theoretically the stronger piece.