Dear Raman ji,
You are absolutely right that there are so many principles and rules that anybody can get confused and make mistakes but then that's with every major scientific field. We know which ingredients to choose to make tea out of thousands

I am out to find correct ingredients for every recipe of life and astrological analysis.
Regarding question in hand, yes, significators will be 2nd house, 2nd lord, Venus (natural ruler and significator), afflicted Mars(my experince says Saturn's affliction is needed here). We can also study Moon cause it shows mind and tiltilation and behaviour pattern. If Moon is under heavy benefic influence of Jupiter then all these afflictions will get nullified and will result in something else.
D-6 should be considered but next to Rasi/Bhava chart as primary indications has to be there. 2nd house in D-6 and D-9 should be taken into account.
Raman ji, occassional, moderate, heavy or addiction are nothing but various degrees of afflictions of the same factor/s.
I request you to give detailed opinion on the chart which I have posted.
Kindly correct me with reasons, if wrong anywhere.
Thanks.......
Best regards
Jai Nahata