I can understand the intent of this SOP but the implementation can be challenging unless, of course, all non essential calls on box 2 (to company etc) are banned during climb and descent but sometimes the only time we can get the ATIS is during the descent and also we need to check whether the ATIS has changed.
Also I can understand the confirmation of the cleared level maybe but (especially in the context of level busts) but I think the flying pilot should be able to set the heading correctly after readback!
Of course experience of the route helps - there are certain times when I will not go off ATC as I know that a clearance is probably imminent.