First of all I might say that production and acting wise this movie is impeccable. The controversy here seems to be about the message that the movie sends. I don't think that this sends an evil message that the poor must kill the rich in order to succeed, no, we must not forget that this is simply a movie and that is also based on a best selling book. Now about Balram actions, we see him being bullied and despised throughout the entire movie, we see that his family only cared about his money and marriage and not really about his feelings or desires. The trap of poverty is what we see in India, everyone is unable to create wealth because the people surrounding are all poor and even if you are lucky enough to get a good job like Balram did they controlled him by forcing him to take the blame for the murder and menacing his family life if he stole, and then after years of work you get too options either you save enough to buy a home or you become homeless, but they can fire you at anytime if they want to like they were about to do with Balram. Now I understand that the master that he killed was the most decent one to him but I dare to say that was impossible for Balram to become rich without killing his master and you must look at things from his perspective as well. First, at the end he was stealing from him with false invoices and got a significantly good amount of money given by Pinky but even in that situation he hadn't got enough to simply quit and start is own business. Second, he was going to get replaced and after that we can assume that we was going to get a more precarious job and start to afford less and we all saw how he lived precariously working for rich people. Third, his family only wanted his money and to marry him and weren't able to help monetarily. Fourth, we clearly see the effect of that lifestyle on Balram, towards the end of the movie he is starting to loose his mind after going through all that and obviously that influenced his decision to kill. So taking this in consideration his only way to escape the cicle was by killing his master, steal the millions from him, change is name and appearance and start his business.
For the people complaining about the confession letter that they had off him and about the fact that the master family didn't go after him he explains in the movie that the only reason that he didn't get caught was because his appearance could be of a lot of average Indian men and he also changed his name so if they were looking for a Balram they wouldn't find him, and he also says that he can be caught one day but it was all still worth it to see how it is to not be poor.
Now the fun part is that at the end, after breaking his cycle of poverty he becomes just like the people that did him wrong because the only reason why his business succeeded was because he bribed the police and acquired some control over them, also becoming a corrupt himself. The good part is that he treated his employees respectfully and took blame for them actions unlike his former masters.
Now you guys can interpret that the message of this movie is in order to be rich you must kill, but I see a much deeper meaning than that. The system is corrupt, the politics were bribed on a daily basis, the rich treated poor people like trash controlling their lives and not caring about their problems, poor people lived on precarious conditions lacking health cares and decent living conditions, the message is that this oppressive system creates people like Balram that tired of being treated wrong and knowing that the future didn't had nothing great for him he did the only thing that in his thinking was his choice. We don't need to educate people to not kill their bosses in order to become rich, everybody knows that murder is not the correct way, what we need is to change the system in order to make people not even consider that possibility, by creating conditions that allows everyone to live a decent life despite everything else. Balram is a product of the system, the big message is: we must change the system!