One more question, is there a luck factor at all ? If I burn 50 coins now, can someone who burnt only 1 get the PoB reward ?
Yes they could, except relative to the guy that burned 50 coins, the person that burned 1 coin would have a 50 times smaller chance of finding a block. Once a pool is made, both will get coins but the 50 coins guy would get 50 times the reward the 1 coin guy will get.