Let me offer a slightly contrarian opinion.
Apply ED to W&M if indeed you have done your homework on all your possibilities and believe you would be super happy with W&M.
But don’t apply ED to W&M if there is any possibility that you will feel disappointed in January or February after you receive your acceptance letter from W&M and are ‘locked in’. Based on what you wrote, you appear HIGHLY likely to be admitted either ED or RD.
Then, really dig deep into your priors:
(1) there are wonderful STEM-focused or schools with strong STEM departments which are not “cutthroat”;
(2) I totally get what you say about cities and large schools . . . but is your feeling just ‘right now’ when you’re 17 years old, or might you see college as a low-risk way to explore cities & large institutions before you commit the next 50 years of your working life in such;
(3) you are absolutely correct to discount “prestige” in selecting a college but the most selective colleges might offer access to a diverse cohort of fellow students that you might find personally exciting and stimulating (intellectually, socially, culturally). Most adults look back upon their time in college fondly as far more than ‘getting an academic education’.