#4 will kill your mental health over time - would not recommend. Take 15 minutes to close your laptop and sit somewhere else. The other suggestions are really good.
I'd say that really depends on what your work environment is like. I've worked places where I'd much rather eat at my desk, quietly reading a book or newspaper, than go into a loud, crowded breakroom/cafeteria where I was either ignored or expected to talk to people I couldn't be myself around.
We don’t disagree, my point is to treat lunch as a complete break (even if it’s just to read at your desk) rather than powering through every day to try and leave a few minutes earlier.