irfanbagus,
It's no so simple. This project has coordinators who decides what will be changed. "Better than" in this topic is relative. He will need to proof and convince that the new is better than the old. Someone which solid background in design can do good changes, but its not enough. The passion of the coordinators of the project created a resistance to changes in visual, if not already started or created by leaders. This is normal. Any creation will be just a suggestion. Coordinators may approve or not, regardless of being "better" or "worse". They are experts in programming. I can not say about visual design. But they are the coordinators.