Using MEAN Stack for social media app and service like fiverr

I'm planning for an application that is a social media app with service like fiverr is integrated where user can communicate with each other and ask for advise.

Problem: What should be the best technology stack, weather it should be MEAN(Mongo, Express, Angular 2.x, Node) or MEN(Mongo, Express, React, Node).

Also I want it to be a REST web app, so that I can develop mobile apps later. So should I use some NodeJS framework like KeyStone or some generator like generator-meanjs. And what should be the directory structure or architecture for this.

Thanks