Creating a Template or Install Package for sub-organizations

I have an organization (ex: “Gardner’s Jedis”) which has hundreds of sub organizations, or “sects”. I’d like to provide a “Gardner’s Jedis” template to each sect, so that each sect has a clean looking site.

I can obviously create a template, but I also want to have control over certain widgets or plug ins – for example, I want to be able to make sure that the sect CANNOT REMOVE a “Jedis calendar” widget, which makes calls to the national site to display a national calendar. I’d also like to make sure they cannot remove an advertisement code block that will make calls to the national site to display a national advertiser.

Simply put, is there a way I can create a “locked down” WordPress install package that will allow users freedom to add their own content and plug ins, but not remove the “default” ones that I provide?

I’d like them each to host the site on their own hosting, however if I have to in order to achieve my goal, I can force them to host the site on my server.

I realize that I can never totally prevent them gaining access to the code. However, I’d like to be able to “lock it down” such that can’t simply click a “Remove Plugin” button.