Which card is the best is little difficult to answer. It depends on everyones personal experience. I am having HSBC&s global Visa card. For last one year I am using this card. Widely accepted. Customer service wise they are helpful sometimes I required doing some follow-up for the service but these occasions are rare.
I have not experienced other banks cards but my colleagues have. Their experiences proved very helpful for me in selecting the card.
I selected this card because of their excellent banking service. Payment wise they are very liberal till date I havent face any trouble related to the payment.
Customer service is very good and reachable from any corner of the world. HSBC card I feel is better than any card
About the credit limit it depends on applicants financial status and is decided by the bank. If the limit given by the bank is not sufficient for the user after six months you can apply for the enhancement of credit limit. Normally credit limit of Rs.30, 000 is more than sufficient and it solve your purpose.