Yes. role 1 can work. I am an "advisor" at a seed level startup. I like to believe that I am useful there. Engineering Team is in India, mostly young folks. They use my expertise for precisely the things you mentioned. code reviews, CI/CD suggestions, system design etc. I spent 3-4 hours on their system. The CEO is my close friend. so it works well so far. I have worked in Walmart, Yahoo etc. The juniors gain my experience of "working at scale"