Lastly, I'll just use the proof everyone seems to use, personal experience: my father owns a 330i and its gears always have a nice pull from whatever rpms compared to the WRX. During highway speeds, when I have to pass cars in a jiffy, I don't even drop to 4th when driving that car (I drive at 65 mph, so that will make a big difference compared to someone who drives at say 100 mph where the WRXs at max torque at 4k rpm).
Er, the reason the 330 accelerates well at 65 in 5th is that it's got torque lower down than the WRX. Since both the WRX and the 330 are turning about 2,500 RPM at 65, it would seem that the wonderful BMW gearing you refer to is equally wonderful on a WRX. The difference is that the BMW has lots of torque at 2,500 RPM while the WRX is just coming on boost. Try the same experiment at 3,500 RPM and the answer is different. I recommend that your either downshift or cruise at 75 so that you don't have to downshift.
But, it could be worse. My now-departed 2001 C5 turned about 1,500 RPM at 60 in 6th....330's would routinely leave it for dead in roll-on's at 60. Of course if one downshifted to 5th the outcome was significantly different. Then, of course, one could downshift to 4th (which was good for 135) or 3rd (which was good for 105), or even 2nd (if you wanted to risk wheelspin while accelerating on the freeway).
Bottom line...gearing is there to optimize for a number of variables, including gas mileage and engine longevity. There is nothing better (or worse) about a BMW's gearing that anyone else's. If you really want strong top gear acceleration without downshifting you might try an STi as they are considerably more optimized than a WRX for acceleration....considerably more so than most BMWs.