The APS question has already been dealt with so I will leave that aside other than to say that I expect APS systems to undergo considerable evolution in coming years and it would probably be short sighted to tie them down to integrating too closely with other things having multiple functions.A thought on this whole RWS/secondary weapon thing.
It seems with bolting an RWS, AMS, sights, commanders viewer, .50cal, 7.62mm and stove pipe on the top of the turret we're getting to the point where we can't see the wood for the trees so to speak. Or at least see the top of the tank for add ons. It'll also have a radar signature roughly akin to my waist line. Equally these will all
(and its beginning to sound about as impractical as the A.19 tank, or the 1938 class medium tank!)
It occurs that we have several problems all requiring the same solution. What if we were to combine these items into single mount?
The APS fire 40mm sized fragmentation grenades to disrupt incoming missiles.
A programmable 40mm grenade could be quite hand in close in terrain to dealing with enemies out of sight or in buildings.
The mount for this could easily mount the Commanders sight as well.
In addition as such a mount would need to be fed by a belt or magazine, it would provide protection against any future developments in drone technology, such as the drone swarm concept.
All of these could be met by a one or two low velocity 40-50mm grenade lobbers.
As for the commander's sight, if that has to be able to be used to aim the main gun then I don't think you want to mount it on the RWS as maintaining accurate alignment would be difficult. You have too many components whose tolerances and motions stack up.
The top of the RWS however may be a good place to mount observation and warning sensors on a short mast.
So far as a near term CR2 is concerned, anything being considered for that needs to be more or less off the shelf right now.