This is a complicated question. First, es7 specifically is very small. It consists of the
** operator and array
Next, while both typescript and babel are popular options, typescript is an option both as a standalone solution and as an integration with babel. So in using babel, you’re not also locked out of typescript. They can work together.
Typescript (standalone) tends to only official features (stage 4) and stage 3 proposals. So you won’t be getting the latest and greatest out of typescript, but you will be locked into more standardized code, which in the end, is probably a good thing.
I don’t know what kind of numbers are out there as far as who’s using what, but my impression is that standalone typescript has the edge because of its ease of use in setting up and getting things running right out of the box. If you’re interested in type safety, I’d probably go with typescript. If you’re more interested in just writing cutting edge js and making sure it can be compiled down to work in older browsers, you’ll probably want to go with babel.