Those that had huge damage impact and made a gameplay less tactical, but blast-friendly, these were: Banana Bomb, Super Banana Bomb, Salvation Army, Ming Vase to name a few, even Holy Grenade and Baseball Bat providing easy surfacekills, all those were replaced with similar, but more tactically interesting and more combo friendly weapons from px roster, that only adds up to the serious fight, also most strikes were replaced with cooler ones from the px roster.
I could write a detailed encyclopedia-lenghty thread about the spirit of kaos and I think I will (posted somewhere in these forums anytime soon), to expose a bit of background and arguments behind the fact that classic scheme development stopped at some point few years ago and it was continued on px for serious players needs.
The principle idea behind it always was and always will be a priority though, whatever it shall evolve into. To provide a tactical multishot action-paced fun for normal-pro oriented players.