Hmm... I think 770 is actually farther from 800 than you might think. And
the OPs goal was to get from 480 to 550. I think unless it breaks the plane of 600V, 480 and 550 are gonna be looked at as more or less the same (not great, but not sub-400). Maybe that threshold is more like 500, in which case the percentile difference is minuscule between 480 and 500. While the percentile between 770 and 800 is actually quite large.
I must say, that I do not work on adcoms, so I can't say for sure. But, I've definitely seen more verbal scores that are below 500 make top 20 programs than I've seen sub 780Q scores get into top 20. That's my 2 cents.