Haribol Krishna Prabhu
While i agree with the main intent of your argument, i feel that one of your
questions is untenable.

>From this account, several questions naturally arise:a) If Vishnu Puraana says
that Krishna and Shiva are the same Supreme Personality of Godhead, then why is
the Lord fighting with Himself?[Kizhakkemadam, Sriram N (MED)] When Lord Vishnu
descended as Srinivasa, he had a fight with Lord Varaha who was occupying the
present day tirumala area. So, one expansion of the Lord is fighting with His
other expansion and this is perfectly tenable as a divine sport. Therefore, the
same argument can be applied to prove Shiva = Vishnu (logically only).
Your servant,
k.n.sriram