Shameless plug - I'm trying to improve upon Elm and React's programming model with my Concur UI framework. Its programming model is a bit unusual, it uses Monads to sequence widgets in time, but it is designed to be extremely simple to use, and you don't need to actually understand Monads to use it. An advantage is that it's not artificially restricted like Elm, and allows you to use advanced Functional Programming tricks when you can and want to.

It is available for [Haskell](https://github.com/ajnsit/concur), [Purescript](https://github.com/ajnsit/purescript-concur), and [Javascript](https://github.com/ajnsit/concur-js) (so no need to learn a new language), and also allows using external React components. The Javascript version uses Async Generators as a substitute for Monads.

With Concur, you can implement the entirety of Elm architecture with a few lines of idiomatic code.

Purescript or Haskell -

    elm render update = go
      where go st = do
          action <- render st
          go (update st action)

Or in JS -

    function elm(render, update){
      var go = async function*(st) {
        action = yield* render(st);
        yield* go(update(st, action));
      };
      return go;
    }