I believe this style is supposed to 'blouse' like Jan said. You might be trying to wear it contrary to its nature. Have you tried "going with the flow"? Blousing it, instead of pulling it down over the hips? (I'm sure you prolly have)
Anyway, other than that, I agree with the suggestion to frog up to the st st, and reknit downwards using st st all the way, ending with a more conventional length of ribbing. The ribbing can still be ultra tall...but not ULTRA ULTRA tall.
This sweater style is fairly conventional anyway, so I don't think you'll ruin its overall 'look'. Besides, the tweediness of the yarn takes the front row anyway. If it was a solid yarn the 'style' of long ribbing on body and sleeves would be more pronounced, and ULTRA ULTRA tall ribbing on the sleeves would make the body need ULTRA ULTRA tall ribbing to balance it out, or carry the theme.
I covet your yarn!
It is wonderful. It's too costly to let it linger in a sweater you won't wear. Been there, done that.
Join the club!
Our question is: why do these dilemmas only happen on expensive yarn?