Overall good changes. But I think that they should just nerf the M10 and Cromwell velocity, which are the only armoured vehicles that allow you to make a massive infantry crush. Also, the MG42 was a nice addition to the doctrines, hope they replace it with a nice ability...
I think you mean speed. velocity include both speed and direction.
and it's not the speed that's the problem, it's the rotational rate. 95% of infantry crushing is really the m10, t34 and cromwell rotating into infantry. Nerf the rotational speed if you want to nerf the crush.
the m10 and cromwell have a rotation rate of 38 degree per second, and the t34 have a rotation rate of 36 deg/s.
the far less crushing sherman, pz4, and panther have rotation rate of 34, 32, and 30. the panther is actually faster than the t34/76 but the lower rotation rate keep the panther from crushing infantry.