Two major strike squadrons of PAF fly Mirage-V aircrafts. PAF uses Mirage III in in Air combat role and Mirage-V in strike role. There are two main issues, procurement and then upgrades. lets look at the three types of aircrafts that PAF wants to keep flying earnestly; JF-17, F-16, Mirage III/V.
JF-17 is being procured and upgraded by PAF. Whenever F-16 is procured, its upgraded by TAI and quality checked by LM USA, as seen in recent past. The Mirages have been extensively upgraded, the money has been invested already. There is obviously the ROSE upgrade, but the rest of the fleet has been upgraded to a certain extent too. Replacing Mirages still requires alot of investment, in the form of a new aircraft, which after procurement will again go through upgrades to reach parity and commonality with JF-17 at least or F-16 if its a western aircraft. The Mirage V which took part in LOC strike were non-ROSE but definitely upgraded.
During an analysis with another member here on PDF (cant remember now who he was). we observed that PAF Mirages squadrons are mixed, which means they fly both Mirage III and Mirage V in same squadron. Mirage III provides AD/escort and Mirage V is used for strike. Basically self sufficient squadron. However, the strike showed something different. JF-17 on escort, Mirage-V on strike, and now since PAF is getting Mirage-V's, this could mean that Mirage III would be the next to go after F-7P/PG's. The importance of Mirage III still holds since Ra'ad ALCM was tested on it. Operationally, PAF has shown that JF-17 and Mirage-V's are set to be paired together in an event of war.
Mirage V differentiates from Mirage III in terms of two more hard points, better rate of climb and a longer nose. Its also said to carry more fuel and more ordnance than Mirage III. The versatility of Mirage V can be seen by the fact that it holds two major dedicated roles in PAF: night time strike and Naval support. These roles are shared with JF-17 and F-16 now.
Coming back to procurement and up-gradation. The plus points in this acquisition is saving cost in terms of:
1. Weaponry: PAF wouldn't need to acquire and integrate new weapons.
2. Infrastructure, training, pilot hours, simulations etc.
3. Upgrading EAF's Mirages V's to ROSE standard is not required since, these can be used as spares for ROSE or other upgraded versions. Basically, if these aircrafts can help ROSE squadrons fly for another 20 years through cannibalism for spares, then this acquisition is worth it.
If they are deemed proficient in terms of lesser flying hours, then yes induction and possibly upgrades are possible. This would still depend, these can be used to replace other aircrafts or can also be used to increase inventory. In the former, replacing systems from old frames into new frames would be done, while in latter, induction will take place with better avionics and systems. Its up to PAF to decide the path, it wants to take.
Regarding Mirage 2000, PAF will see feasibility from all pov's. Cost of induction, infrastructure, upgrades, weaponry, training, simulators and finally frame life. F-16 still has production line running, it has a major MLU plan in process, not just M-3 or M-5 but also V-standard now. JF-17 has newer blocks coming in, probably upto Block IV. So cost wise., Mirage 2000 will always be costlier. Comparing capability, yes Mirage 2000 is much more capable than Mirage V. So Mirage 2000 justifies its cost vis a vis Mirage V, but compared to F-16 or JF-17, their capability comes at a lower cost than Mirage-2000. The Ra'ad issue still exists; which can be solved through a different platform or redesigning the ALCM itself.