While of course I will concede to my more learned Brethren, I personally see no problem with an EA wearing a ring. Because, at least in my Lodge, we stress that once obligated he is a Mason, period. His degree within the Craft is something entirely different. After all, is a Private less of a soldier than a General? Perhaps the private soldier shouldn't be allowed to wear a uniform because he hasn't attained a certain status or level in an army?
Masonry is a lifelong following, to set artificial barriers is, in my humble opinion, somewhat narrow minded. We are constantly learning and searching for more light and in a great many cases, although a brother may wear a ring or fancy trappings, he is not a Mason. If bling is a cause of concern and contention and must be "earned", perhaps we need to reassess what it is to be a Mason.
My two bits...