Are there any good JS libraries that take more Unix-like approach, i.e. they do one thing and they do it well? For example a library that would implement just the Model part: syncing data between server and client. Or another one that would implement for example a better abstractions for event handling (event-firing states, futures, etc.), but nothing more.
I think the problem is mostly that a todo list is too simple an example for these frameworks and that's why it seems like they're just adding extra structure. That extra structure is (hopefully) going to save you a lot of code once your app gets more complex.
It's all well and good to keep it simple if the extent of your app is actually a Todo list, but most of these frameworks are built to render an entire website worth of content on the client, including a router, controller, models, views, etc. That necessarily can make them a little more verbose for these simple examples, but invaluable in giving structure to complex apps.
Backbone does that , you can just use one part of backbone without the rest. want are router ? use the Router , want models? use the Model object ,want just sync ? use the Sync ect... backbone is not a MVC framework it is a collection of tools. Backbone doesnt force you into anything. That's why there are no controllers in Backbone ( Routers are not , routers are mediators ).
Are there any good JS libraries that take more Unix-like approach, i.e. they do one thing and they do it well? For example a library that would implement just the Model part: syncing data between server and client. Or another one that would implement for example a better abstractions for event handling (event-firing states, futures, etc.), but nothing more.