I say this every time I see a college list with Williams in it: I highly recommend adding my school, Amherst College, to your list! Very similar vibe, student body, and level of prestige (they’re often deemed the two most prestigious LACs out there). Amherst has extremely strong departments in philosophy and math (my Amherst friends will NOT stop talking about how wonderful their math professors are), as well as your other areas of interest. The open curriculum also ensures that you can explore all of your interests even when you commit to one or two majors on your list!
Also, consider adding Middlebury. Similar to Bowdoin in a lot of ways, though less selective (which is good, considering how selective all your current reaches are!), and with VERY strong philosophy and math departments (my brother actually double-majored in those two at Midd, and LOVED both programs).