V1 will also increase with weight, since it's not just the accelerate-stop distance (e.g. field limit weight) you have to worry about. Passing V1, the airplane has to be able to maintain the centerline and accelerate to Vr with one engine inoperative. CS-25 requires that V1 is at least equal to Vmcg (minimum control speed on the ground), and the Vmcg just as Vmca (minimum control speed on the ground) increases with weight.
V2 again increases with weight, since it has to be equal to at least 1,13 * Vsr (reference stall speed) and 1,1 * Vmca. As Doodlebug pointed out, stall speed and Vmca increase with weight and so does the V2.