Finding the right level of abstraction for the tests is important indeed. It helps keep them useful longer. Scope and complexity are linked and can help find the right balance of tests.

It's fine to surround yourself with people smarter than you. It's a good thing... except if they are competitive. Then it can become a curse and kill your motivation.

For technical tasks, the user stories common structure (the "Connextra format") is not adequate. We can indeed take inspiration from other long forgotten agile approaches for alternatives. I particularly like this one, and it works for user stories as well in my opinion.

Definitely the right rule to follow to designing classes in C++ in my opinion.

This is a good pattern, use it! This article does a good job showing variants and where it makes sense to reach out for it.

Looks like a nice tool for UX design and getting insights from conversations with users.

Nice explanation of what Bloom filters are for and how they work.