You do seem to have a consistent hips-forward pose, but that may be your subconcisou reaction to posing for the photo. If this is your naural pse you will need to shorten the back rise on the pants, I think. It is not the taper that looks bad, it's the bunching behind the thighs, in my opinion.
For suspenders I would look at ebay. They mostly go for peanuts, so why pay retail?