That is certainly another approach they can use. AK-2 can be the longer term replacement for AZ and other types, since the amount of VT-4s PA is getting is enough to replace Type 59/69.I think AK2 could be the 'next AZ' -- i.e., a low-cost force builder. Ideally, the PA would want to apply the VT4's engine and electronics, but add to the armour/protection without cutting into mobility.
if they don’t do a redesign, only add some tech from the VT4 on top of AK-1 and keep it a relatively lower-cost upgrade, it will still be superior to basically everything in the PA fleet except the VT-4. (I doubt they will replace FCS, GCS and thermals, AK-1 already has pretty good local ones, and if they add a CITV it will likely use a Catherine or Matis TI from shibli as is used for the gunner)
Considering they’ve shown interest in replacing it’s engine with the VT4s engine, understandably so, that will be a massive increase in mobility. To put it into perspective. The 6TD-2E engine makes around 2800 NM of peak torque, the HB150 engine in the Pakistani VT4 and Chinese ZTZ-99A apparently makes closer to 5500 NM of peak torque (The Perkins condor engine, one of the engines that was also being originally considered for the AK made around 4000NM of peak torque). The 6TD engines are notoriously underpowered, and I suspect that has led to at least some constraints in the amount of stuff that can be put on AK especially, in terms of ERA/protection.
Maybe they have also considered the option to put the HB150-1200 engine (1200HP but would have a torque increase over 6TD-2E) in the AK-2, the one that is present in the normal VT-4s, it would still be a large power boost while keeping down fuel consumption and cost. The AK is a few tons lighter than VT4 after all.
They need to do something with all that added power, even if they don’t redesign the tank, it is likely they might put FY-4 ERA on the hull and turret (which without a turret redesign would not be a lot of ERA, but it’ll be better than the current one). They have also shown interest in polish ERAWA in 2017, and Ukrainian Nozh/Duplet during the oplot trials as well as during COAS’ recent visit. I still feel like it should at least get a turret redesign
Other than that the technologies from the VT-4 that can be adopted are the Auto-boresight, newer Data-link and more stuff on the electronics and software side, especially in regards to the BMS and C4I.
If PA ever does want to make a local next gen tank, which is really not needed anymore after VT-4P, it would be best to start from a new design.