The idea behind timed abilities for QCQ unit is that these unit are rather difficult to balance and this could provide a solution.
They either seem to bleed too much or rolfstop enemy units. A timed ability would allow the unit to be good but only a limited time.
Agreed, but diversion is currently not worth the cost over sprint. The buff I suggested might be too strong tho, now that I think of it.
The idea behind PzIV switchable munition is not to increase the AI but the AT, similar to 76mm Sherman. The PzIV have trouble penetrating anything above allied mediums and this change could make the Panzer H better vs those units.
IMO, Ostheer doesn't need a generalist option for both AI and AT. The option to skip to T4 with the Panzer 4 H already opens the door for an easier Panther afterwards.