You can create your project with create-react-app and when you feel comfortable, you can type npm run eject and modify your code as you like

I use the grid system based on bootstrap (sm, md, lg) http://getbootstrap.com/css/#grid

I use Flexbox only when is impossible to get the wanted result without it (from a easy way with pure css), for example, making a div vertically centered.

You can invite a friend to work on a side project with you, even if he doesn't know how to program, only the fact that you will have someone looking at the project that you're doing, will help you to keep motivated.

It's almost it that i'm looking for, thank you

I don't see so much benefits, only one on a first view, the possibility to extend you app after, for example, you can create a Android App that consumes your API, or, maybe another people can create their websites that consumes your API too.

Ah, sorry, i'm already using Spring Loaded, but 70% of times that i try compile the code the server crashes, and i need restart it, when i do it my session loses it scope and i need login again. So i have some easy way to do the first option? (you have a basic example or something like?) (Jrebel isn't a option, so expensive =x)

(just additional information) Like @josfaber said, isn't secure if you open your data to all origins (*), so, to get around it if you don't know exactly where is the origin of the requests you can create some kind of TOKEN api.

I already have a login system to access the API, this behavior is just to prevent the intern users from enterprise can access data that isn't permitted for they. I didn't remember this thing that you said, thank you, i'll take care of this point too with some permission system.

Thank you (: