Auxilliery fighters

On my “define LIFT” thread,Ive discovered that the new generation of “trainers”(mig-AT,Mako,K-50) purpose goes beyond LIFT,and are a sort of auxilliery practice aircraft to save wear and tear on front line fighters.Ive suggested to people in the past that the F-5 should be put back into production because it is an extremely economical second line fighter/attack aircraft,and everyone scoffed at that idea.I contend that jets like the F-5 and sepecat Jaguar would make an even more economical LIFT/advanced trainer/auxiliery practice aircraft as well as making a potent second line combat aircraft.Before I was asked to leave the chingkuo thread,I sujested also that the jaguar was equal or better to the chingkuo,which I rate as equivalent to these new generation “trainers”.Your responces?