Yes, that's perfectly right!

I think, even if you know enough JavaScript, you still have to learn the framework you're using and the standards and practices defined by that framework's community, it won't come magically, at least for me.

Of course I recommend it. This track is taught by Guil Hernandez who is very talented and one of my favorite teachers. But I'll suggest to first try Treehouse through 7 day trial , and see if it works for you or not. Before jumping to React, make sure you know enough of JavaScript (and ES6). There is a JavaScript path too at treehouse, but I'll recommend following Eloquent JavaScript (book) , and/or the modern JavaScript tutorial which felt a very good tutorial to me (as I just skimmed through the content). Otherwise if you like following video courses more than a book / text, then follow their JavaScript path before React path. If you already know enough JavaScript, jump to their React path directly. I wish you the best of luck!

I'll choose Elixir 10 out of 10 times until I'm forced to use Go.

With my mackbook I use an external screen (while I'm reading a book/doc/blog and coding the examples and exercises) as my macbook has smaller screen and both the book and code editor/terminal don't fit at the same time, but with my other laptop with bigger screen I don't use external screen. So both the 3rd and 4th options are true for me.

I think Ruby solutions are the best. You can generate API-only application by just adding the --api filter to the rails new command. Sinatra is also a good option for APIs. Ruby itself is the most expressive language. With the release of version 2.3.X (and above) Ruby improved its performance a lot, combining this with Puma will give you a nice performance and concurrency combined with the maturity of Rails (or Sinatra). If you're looking for multiple times better performance than Ruby (or Node) but still a codebase which is highly manageable and simple, then go for Golang .