I think the first postal card is the most interesting. I am not sure I understand the received cancel from Bombay. Bilimora is a port town in the Gujarat state.
Golden Temple cancel is rather common.
The postal cards are typical condition for India.
The Khairabad cancel if I am reading it right is from a town in the Uttar Pradesh, and was probably a smaller town in the teens. Might be scarcer. The received cancel says "Window" I think which is intriguing.
Concerning the 'WINDOW' delivery mark, this method still exists in India:
"Except where the post box system is in force, any person residing within the ordinary beat of the postmen can have all letters and other postal articles received to his address delivered to him regularly, during business hours at the window of a post office, free of any charge on this account provided that the articles are taken over loose and that the addressee makes a written application to the post office asking that his letters and other articles may be retained in the Post Office till called for, instead of being sent out in the ordinary course through the postman."
Everyone else has covered these pretty thoroughly already. The only point I can offer is that the Khairabad CDS has 'Kotah' in the bottom of the ring. Kotah was a large State in Rajputana (now Rajasthan), so I don't think it can be the Uttar Pradesh Khairabad. Incidentally, Kotah State issued its own stamps for a short period, well before the time of this postcard: the stamps are distinctly scarce.