Considering the fact that we had 3 major career paths like reseach / teaching, commerce and governance (including security) which are supposed to be the 3 varnas, there should be specialised gurukuls for each of them.

Like say Dronacharya, Parashuram, Kripacharya, etc were Institutions for training on Kshatriya dharmas or Governance aspect which ofcourse inherently included warfare techniques. Only students from these institutes were recognized for any considerations.

Definitely for other two also there sjould be gurukuls, where higher knowledge based researches were done in some and commerce based knowledge in others

Do you have any knowledge on this ?