There are many ways to point out problems, it seems your problem is how others took the suggestion. This may have been something that others did not want to see the light of day. Was your problem with the PTO (which you have control of) or with the admin. or staff (which you should not have control of).
To give an opinion on what you should do we could all use a little more information. Ultimately the PTO is an organization in support of the children AND the school.
