I do think that this idea would throw the game way out of balance. i can normally get 2 or 3 of the extra bosses as it is. sometimes I have a crappy run and only get one... but I mean, thats the way the game goes. It does keep a bit of balance as far as lab goes with VIP players/non VIP to have it the way it is. I am VIP 2 and get a 3rd run at lab if i so choose to. It would benefit me more than a non VIP player to change it, BUT for balances sake I think that it is better like it is.