Bigg Boss has maintained its controversial essence since season 1. Friendships, fights, manipulation, love, argument, politics you name it and it's there in the show. Due to this reason BIGG BOSS is so popular in realty shows. People actually like seeing the connections/ break ups/ fights in the house.
Show Host plays very important role in balancing things in the house. Due to the show host only people inside the house got to know their mistakes. In my opinion, star power is really required so that people inside the house at least listen to the host and try to rectify their mistakes.If the show host is of the same level as celebrities inside the house than no one will listen to him. Yes I agree, there are exceptions like Juhi Parmar, Sky, Pooja Misra, Pooja Bedi, Sapna Bhavnani, Imam, Kushal and Gauhar. But I feel even these people behaved little decent because of the star power like Salman Khan and Sanjay Dutt. My point is that, its a human tendency to treat a same level person lightly but when someone from the higher level comes atleast they listen to him once.
Star power is definitely required to run these types of show. However, I also feel that show host must act neutral irrespective of his personal connections. The show host's duty is to guide the contestants and not to threaten them.