None of 10 of points you have raised bears authenticity.It is all just hear and say, rumours, misinformation, misinterpretation.
Nationalism,sacrifices,loyality,sincerity of Sikhs/Punjabis have never ever come under question in the history of India.
All the communities living in pre and post independent India have made a positive contribution to their capacity and expertise.
Conflict starts when a particular community tries to hijack the credit.
It were Sikhs who were sympathetic and reasoned with misguided (by ISI)Sikhs in Punjab from late 70s onward.So naturally and automatically they pushed themselves to second berth.
It were those Sikhs responsible for killing PM of nation followed by distributing sweets, celebrations,hurting the emotions and feelings of fellow citizens, responsible for riots in Delhi and elsewhere.
Sikhism as a religion and Great Sikh Gurus have not preached so.All Guru Sahiban were Hindus protecting Hinduism not asking Hindus to leave Punjab or face death !!! They did not collaborate with muslim invaders but fought against them sacrificing generations. They did not preach to kill fellow Indians for the waters of Yamuna,they did not ask for Punjabi Suba.Their India was from Nanakana Sahib to Mecca, from Anandpur Sahib to Nanded and so on.
Let we small people not disgrace our Great Gurus who were distinct Godly people and Saint Soldiers on this planet. Sat Sri Akal.