I'd suggest that it's not so much the particular words, it's that all the "oddball" words in the sentence are directly Latin-derived -- garrulous, taciturnity, voluble, reticence. This is what gives the sentence a somewhat forced tone - perhaps a good Anglo-Saxon term might provide a punch.

Probably the stock phrases, "collecting friends", "some measure of X", "all but the most", "style is contagious", don't help either.

The quoted words don't seem that well-crafted, but the content of the observation serves as a good character sketch.

Your friends are probably very garrulous. :)