3 weeks ago, I had a new pet project, and decided to go with Python again, which I left many years ago, before Python typing was a thing.
I didn't know where to start, so I started by creating a file with data models I would need. Basically C struct-like / record models. All the classes inherited NamedTuple, and I typed all the attributes. I then created a few pure functions based on those classes. NewType is a great addition. When you work with many int or float variables representing different things in real life (price, amount, quantities, etc), it makes the code cleaner and catch some mistakes when you are tired at the end of the day.
I gradually stopped to type things when I introduced pandas into the project and types started to be way more abstract. There is probably a way to make typing work with pandas, but I wanted to learn pandas first and get the project running, so I didn't really try. I expected pandas to do dynamic things under the hood to work, so I didn't bother to understand how types work with it.
Of course, being a hobby project, there is no unit test and no documentation, so I may not see all the pros and cons of typing. But I have a feeling gradual typing is an interesting idea that will continue to improve.
It's nice to have the support of static typing when you need to, but also be able to "just hack" a solution real quick when needed.