I think that pledge activities are about building the bonds of sisterhood. I don't see the point of this exercise. We had a sorority on campus that wouldn't allowed their pledges to wear makeup during 'Hell Week' and it was not to show their natural beauty. It was to be mean to the pledges. I think that you don't need that in NBO.
I have found that it is better and easier to prevent a problem than to break a bad habit. I think treating your pledges disrespectfully can potentially become a bad habit and is best avoided. Your sorority should engage in team building exercises that teach mutual respect and emphasize the values that your sorority holds dear. I'm sure that there are many greeks here who will be happy to give you some constructive ideas for pledge activities. Think of your long term goal - affiliation with an NPC sorority. Don't do anything to jeopardize that. An allegation of hazing or being mean to pledges can be detrimental to your future. Stand firm on this one.
As far as feeling unappreciated, it goes along with being president or any other position. As the president, it is your job to lead and stand firm even when popular opinion goes against you. You need to have a clear vision of NBO and translate that to your sorority as clearly as you expressed it here in your earlier posts. Cheer up, Corina! Look how far you have come in only a few short months. This is just a little speed bump on the road to sisterhood. Hang in there!