Correction for point no. 9

DPO's reporting officer is DIG/RPO while the counter signing officer is IG. Home Secretary has no role. IG is the ex officio secretary of police department. Plus, he is a commander of force. Mostly IG's are way senior to the HS. Moreover, in most of the provinces the IGs are senior to the Chief Secretaries in service. Punjab's IG is from 1st ctp while CS is from 2nd ctp. Sindh IG is 1970 batch while CS is 1972 batch. What i intend to elaborate is that Police is not subserviant to home department.
The bottom line is that both services PSP and DMG have its pro and cons. Officers of both service command a lot of respect in the society and they are two of the most important services of the civil bureaucracy.