[SomeoneWeird]

I lot of these things are basically irrelevant if you use ES6/7.

[nailer]

Most of it's good, just a cleaner JS, but it'd be better to drop the classes and lambda-type short function syntax in favour of ES6 classes and arrow functions.

[cpursley]

Are brackets and semicolons now optional in ES6/7?

[benaston]

Semicolons have always been optional. Brackets are only used for array literals (oh and destructuring assignment) as far as I know (and are required).