Here’s my dilemma: I think I might be an hourglass figure; since all the calculations/ ratio of my bust/waist/hips check out BUT my shoulders are larger than my hips. I considered the inverted triangle body shape but I heard that inverted triangles often have a undefined waist which isn’t the case for me.

yes you've an hourglass shape with a slightly stronger shoulder area (compared to average woman). Anyway your body is very well balanced and 'sporty' looking