I don't know about halters being good for busty women, but I've always heard they are supposed to be good for broad-shouldered (strong shoulder line) women. Something about the halter creating the illusion of narrower shoulders? Certainly better look than spaghetti straps.
However, I have never had much luck with halter tops.
I think for me the issue is more about fit than style though - even in a petite size, I am shortest from shoulder to top of bra band, which is right where it counts most for a halter top to fit correctly!
I do have a halter-style bathing suit and since I can tie it tight as i want around my neck, it seems to work okay - and by tying it really tight, it does lift the "girls" and give adequate support. (At least, as much support as I'm going to get in a bathing suit!). However, I'm not really happy with how it looks from the rear view: probably my worst feature is my upper back. Luckily, I can easily ignore that part of my body.
But in general halter tops are a style I tend to steer clear of... because 99% of the time, they don't work.
As for shoes - I have most definetly given up on thongs!!! I can't wear them without excrutiating pain on my one foot. Culprit, as far as I can tell: my toe on one foot turns in too far. Theoretically, a thong should be good for this (would force the toe back into proper position). But, it just hurts too much. So I give up!
I also gave up a long time ago on heels higher than 2 inches. Not good for your back, highly uncomfortable, and I walk funny in them.
And I've given up on khaki slacks ... but that's probably a GOOD thing, style wise.