This is not the first time a P-16A has had a accident. It is a 60s design after all. I didn't say they were useless but they certainly are risky to operate. The money spent on repair and OH could have been better spent on more NGCs, for example. Better bang for the buck.Second line ships are the ones that allow the first line to do their job without distraction. Just because it does not have fancy weapons or sensors doesn't mean it's useless. Remember, Pechora did a good job with Akash.
Imo, re-engining only makes sense for capital ships like carriers with 50+ year design lives.