Just build in what you know.
Yup, I agree.
The apparent difference in our situations is that you know React and everything that comes with it. It seems like that'd be a good choice for you.
I'm not proficient in any of the currently popular frontend architectures. Gaining that proficiency and moving a 10+ year old product to a SPA type architecture would be a massive investment. I enjoy learning new things and pushing things forward but I can't justify that investment when it comes to the frontend. Instead, I invest in other areas to move forward in.
Best done as an employee is spot on.
Sometimes that might be your employee, and sometimes that might be you.
I guess it depends on where your passion lies, and what your objectives are?
I imagine that achieving one's financial ambitions in a relaxed and enjoyable work environment is great - irrespective of which part of the stack one enjoys tinkering with the most.
I usually assume a role like engineering manager and learn from the teams feedback, challenges and commits
Making money, getting tax deductions and sometimes research credits