I have observed the same thing, Shu -- silhouettes that follow my curves, especially on the bottom, tend to look the best on me. I wear a lot of sheath dresses (which I love!! So easy to just put on a dress and some tights and shoes and be out the door!) and pencil skirts. I've been able to wear some non-sheath/pencil (a.k.a. not curve-hugging) skirts and dresses, but the cut has to be just right. A-lines made out of fairly stiff fabric work well...as long as they don't get too "floaty" they flatter my hips. Pleated skirts I have to take on a case-by-case basis. Sometimes they look great but more often they throw my proportions out of whack.
On the top, I have to be very careful about keeping a defined waist or I end up with a very boxy look or I look pregnant. I go for longer cut tops or peplum tops. Surplice cuts also help keep the waist defined and the proportions balanced.
Some other hourglass gals are okay with not defining the waist but I feel my bust is so large that if I don't it makes me look really topheavy, like I'm about to fall over if a breeze comes along!
With pants I like to wear trouser cut or boot cut at the very skinniest. I wear a lot of trousers (non-denim, that is) and sometimes go for a high waist because it allows me to tuck in a blouse but still keep a defined waist. I find that the wider cut on the leg balances the curves up top very well and looks better to my eye than a skinny pant that can make the ankle seem so much smaller than the hip, and therefore top-heavy.
Overall I've found that if I stick to 1940s and 1950s-inspired looks (not necessarily vintage in feel, it can be totally modern -- but the same silhouettes as popular 40s/50s styles) I can't go wrong. The current trends like very large, flowy sweaters, skinny pants, and cropped top hemlines just do not flatter me.
I hope that helps!