Actually a few weeks ago there was a big movement in the React community about that. The problem is that the JS community is too big and people use different build systems and tests frameworks, let alone coding styles or project/files layout.
I think only Ember has been able to have a strong set of conventions, mostly thanks to ember-cli[1]. I consider it the Rails of JS.
That said, I am looking into nwb[2]. Looks fine for personal projects.
Agreed, the lack of project structure is in my opinion the biggest issues when building React apps. An interesting discussion on project structure can be found here: https://github.com/mxstbr/react-boilerplate/issues/27
Yeah I think it's one of the least talked about conventions, and unfortunately there's a lot of debate because of how React is (CSS next to component or in its own place?, etc).
Coding styles is a solved problem. Use the feross/Standard tool or SemiStandard equivalent (ie if you prefer semicolons).
Structure arguments will continue until the past decade of brain damage caused by trying to shoehorn MVC into front-end frameworks wears off.
The future is self-contained, reusable web components. Organize the structure by feature. Provide a root file that acts as an exports facade that maps the internals to an easy-to-understand public API.
I think only Ember has been able to have a strong set of conventions, mostly thanks to ember-cli[1]. I consider it the Rails of JS.
That said, I am looking into nwb[2]. Looks fine for personal projects.
[1] http://ember-cli.com
[2] https://github.com/insin/nwb