Many children's rights activists have been distinctly opposed to Montessori schools because they change about 1% of the hierarchical structure in schools. That doesn't mean you won't find improvements, it just means that you have been very involved in the community and aware of the process so you can have a greater influence over keeping the standards of respect and freedom high.
Dr. Peter Gray is one of the most adamant critics of Montessori and instead gives The Sudbury Valley Unschool as an example. https://www.youtube.com/watch?v=Bg-GEzM7iTk
Sudbury Valley Unschoolhttp://www.sudval.org/
Mike Lanza takes it a step further and looks at problems within the very framework of our neighborhoods. They aren't designed for children's needs or interests, and certainly don't resolve the fears of parents who won't let their kids be autonomous. Lanza took it upon himself to connect the families in his neighborhood and turn it into an active connected community, which he calls a Playborhood.https://www.youtube.com/watch?v=_Q_wagjIqY0
What Lanza has done is the first step into the unschooling potential of our future. Interconnected communities that phase out the irrelevant harmfulness of the child prison system.
Beyond that, if we reject child labor laws, kids can get jobs and interact in the market, or even invent jobs and build skills and connection into the market much earlier, much better.
It's far better than taking an abused kid from a broken family, hyper-sheltered home and school after 12 years and throwing him in the middle of the market, after indoctrinating him with worship for more school that will now cost him $50,000, and he'll likely spend that debt on medicating pain and trauma through a fun degree in the arts, screwing himself into indentured servitude thereafter.