If you earnestly want to be a change maker, ask your next employer this question in your first 30 days.
Where within the company, can I explore heretical questions that could threaten the business as it is - without contaminating what you're doing now? - HT Warren Berger, A More Beautiful Question
If your boss is a good, they'll not only direct you to where but also set you up with the processes and protocols for being the heretic.
A word of caution - don't allow your desire to make change to interfere with your early stage apprenticeship. You have to learn how to play the instrument before you can start writing music.