Looks like you were at about 1.9 watts per kilogram for that ride. I believe most Cat 1/2 riders (is that the right barometer for "elite"?) can put out about 4+ w/kg for sustained periods of time. While a leisurely century is not the best benchmark, I'd guess that you have a ways to go before being "elite".
Out of curiosity, what kind of power meter were you using?