I have recently started my project using mern 1. Regardless of what mern 2 will offer, mern 1 is the best scaffolding tool for you to begin with. It is the only scaffolding tool I have used to provide JUST the tools you need without useless extras and without unnecessarily complicated code. It's also not too opinionated.
I felt so comfortable from the start with mern, that I immediately got rid of mongo and replaced it with Postgres.
I strongly advise you to jump right into mern 1 without waiting for mern 2 for two reasons:
1) it's already a good scaffolding tool, and once your project grows bigger, you will expand it yourself anyway, and you will be confortable to adapt it to your specific needs
2) Why wait for mern 2.0 and lose time? It's not like you will actually learn any new major technology (although I have to admit, there have been some huge improvements). The goal is to use scaffolding tools as a headstart, and not as a programming paradigm. Best thing to do is to take mern 2.0 once it gets released, see what major changes it has sustained, and try to take the most important ones and implement them into your own project that will be derived from mern 1, if you care enough about them.
On the other hand, if you are operating on a deadline, and you want to be sure that you will use the latest and greatest tool from the start without having to consider upgrading in 6 months, I would advise waiting a bit more.
I hope I helped.