No one cares about your ideas. They care about what you do with those ideas.
Figure out how things work. Figure out why things are the way they are. Learn like crazy, and never stop.
Learn how and where you can make changes. If the structure isn't working, ask yourself why: Is it the people? The assumptions? The processes? The philosophies? What can be changed? (Everything can be changed).
Look at all the things that you can change, and pick the one with the most impact. Where will your energy be most useful? Focus on repeatable, incremental change.