The new Glimmer engine in Ember.js gives you React-like DOM diffing without the use of JSX, and baked into a very organized and easy to grasp framework to boot.
Ember might be well organized and a great framework but I'm not sure I agree with "easy to grasp". There is so much automagic that when something tries to deviate from the common Ember patterns I worry that you are going to have a bad time. I say that having hardly used Ember outside of the intro tutorials so please someone correct me if I am wrong.
While I like the tooling around Ember, I don't know how much I actually like Ember itself. I mean, there are routers, controllers, templates, views, and components. How many different concepts do you need?