184 Mirage -- I couldn't wait to see the Iraqi Mirage jets blown out of the sky in the desert war. Consider these to be 184 coffins should the fighting ever begin.
They are better than the MiG-21 variants the other half of the air force flies. But you are right, they are quite old planes. The Israelis used them well, but that was 30 years ago. They only have 32 F-16s that are better. While the Indians have a somewhat larger cutting edge of modern Russian planes, and can match the Mirages with MiG-23s. They also have hundreds of MiG-27s and Jaguars for duel role and strike. Those reasonably modern planes match the size of the whole Pakistani airforce. Then the Indians have a second line as big again, flying older MiG-21s.
To win in the air, the Pakistanis will have to beat modern MiGs and Sus with F-16s at 2:1 odds; the MiG-23/27 and Jags with Mirages at 2:1 odds, and Indian MiG-21s with their own Chinese versions of the same plane, again at 2:1 odds. In the past, the Pakistani pilots have been somewhat better than the Indian ones, one for one. But it is technologically a tall order. Especially when you consider that half of the Indian force is radar-homing AAM capable, and the Pakistanis don't have one radar homing firing platform in their whole air force. (The F-16s could, but they don't have the missles). So the Indians will outrange them.