This game is fun, and I'm kinda new but you should not have elements of the game that are simply out of reach for people who dont want to spend tons of real money every week. If you lower the boss health at least some people (me included) will have greater enjoyment from the game. Also the people that want to spend tons of money every week will still get ahead and encourage them to keep spending (much like boss items for sale from stolen box).
You have taken the fraud away from bosses by preventing boss hopping but dont take the fun away just simply lower the boss's health! Please.