I am a shorty at just 5 feet 8 inches. I tend to weigh in Kgs, but I know that when I lost my weight before I found it very hard to get into the healthy zone (although I did do a lot of running at that time too, which meant I had a lot of muscle). When I did get below 25 bmi, when I look back at the photos I looked really drawn and skinny.
I think around 75kgs is right for me, although that technically makes me in the overweight category.