One of the most important tenets of religion is faith. This is usually taken as a complete belief in God and his plan even when faced with evidence that contradicts the held belief. The catholic church however is not God. It is an organization that is run by people. If other people of the same religion have a dissenting opinion with the practices of the church as it relates to worshiping God they should be free to express that opinion.
Yes, the Catholic Church should be more open to dissent. Since its inception, the Church has largely refused to pay attention to people who have spoken up against it. This attitude has largely been to the detriment of the Church. The only way for it to grow and expand is to be more receptive.
The Catholic Church has undergone major changes in recent years, especially with Pope Francis as its leader. Francis has made sweeping reforms in attempts to reverse centuries of stagnant rules and doctrine in the church. He is more open to gay marriage and condemned the church's hard stance on abortion and pre-marital sex. He is making the church more open to change every day.
The bible is meant to be followed, you can't just pick and choose which bits of it you like. If you want to follow it then you have to believe all of it, even the disgusting evil parts. If you don't like it then you shouldn't be part of the religion. If the church becomes more open to dissent then it invalidates the bible and that would lead to the collapse of the church.