Brown full ride should be a no-brainer. 
I understand why it’s not, but
Here’s what you wrote about UCLA:
So, in short, compared to Brown, it’s more expensive, it won’t be as good an academic experience, and it’ll hinder you in your career path.
Pretty big cons.
Seriously, UCLA is a great university, but it’s a large university suffering from state budget cuts. The difference in comfort, resources, etc, will be tremendous compared to Brown. For instance, you won’t have a personal adviser at UCLA; at Brown, you will. You won’t have classes you have to take but can’t get into (unless they’re at unfavorable times) and difficulty in taking the classes you want.
And your pros are essentially keeping things like they are in HS: close to home, with HS friends, and a place + weather you know.
I’ll grant you the weather point, but everything else shows that you’re just having cold feet.
College students who enjoy college rarely go home, even if they live nearby. High school friends get to college and move on - or, if it’s really a strong friendship, is stoked through Skype +FB and occasional visits, like for adults. When you’re 20 you’ll probably wish you’d gone and explored a bit, rather than stayed near home.
have you visited Brown? if not, email Admissions and ask for them to fly you in (indicate you were admitted, are thrilled, but it’s very far and your family can’t afford to send you to visit, so might they be able to help you pay for the plane ticket?) They have funds for that and are likely to say yes.