I've been meaning to learn TS. I've done some baby stuff with vanilla javascript in the browser, but I haven't had a chance to really since my teeth in with types in a meaningful way besides just toying around. I'm a Python dev by day. It'd be nice to have the top 2, you know? :)
Yay for #1, lol! TS is great but the way to adopt it is only when you have your own need. The best use case is making an interface for a function of your own. That way, you can be sure when you write calls to that function, the arguments are what it wants. From there, you'll see other places where tightening-up the types can be of use to you -- but the secret is to only use it where it is of obvious benefit. It's all fake and goes away at build time anyway!