Do you wear a bra? When I’m going out for more than just a quick jaunt to Circle K, or to drop kids off at school.
Size? 34-36B, depends on the brand.
Why or why not? Why? Well, when I do, it’s for support, as far as appearance is concerned. I don’t think they look bad, but they’re a little more teardrop shaped since having kids, so a little guidance is nice. Also, I have, um, err…PENS(Copyright somebody at the ULMB), which is Permanent Erect Nipple Syndrome, and above, and beyond that, I have exceptionally large nipples compared to your average woman(oh the comments I’ve received!) so, I kind of like to be able to go out, and say something to, or even just stand next to, a male, and not have him think that I’m happy to see him, or extremely cold. 
Wear a bra to bed? The only time I have ever worn a bra to bed was during the post-partum period of my three deliveries. I breastfed my oldest for a month before I had to quit, and it helps with engorgement, as well as holds breast pads in place for the leakies. With my younger two, I wasn’t able to breastfeed, so I was instructed to wear one, tightly, all the time, to suppress lactation. You also do a fair amount of leaking during that, as well, so… BUUUUUUT, lactation issues aside - nope, never, not on your life!
Casually around the house? If I’ve already been out, and was wearing one, I won’t automatically take it off when I get home, unless I change clothes. If I’ve just done one of the quick jaunts listed above, or am staying home for the day - no way!
Favorite style? Simple, plain, cotton. No padding, but definitely lined - see PENS above. At some point I ended up finding an underwire bra that I liked, and I’ve worn 'em ever since. I’m picky when I shop, so I haven’t had many problems with discomfort, and frankly, I feel odd without the wire. I did wear wireless bras when I was pregnant, however.
are your breats proportional to the rest of your body? Yeah, I’d say they are. I am petite, so they look quite natural, although they’d still look fine, and proportional if they were a little bit bigger, they’d probably still look proportional if they were a little bit smaller(though I don’t want to find out, the small loss of gravity I’ve already encountered is enough, really), I think I’m probably just about right for my measurements.
There ya go, all you ever wanted to know, and most likely much more, about V’s boobies! 
~V