Cant afford a good one though. I see soon many G's and AG's but not much else. Doesn't seem to be many of these in higher grades.
Conjecture: Since it was first year of issue for the series it may be in the same situation as 1909-SVDB Lincolns. Many were saved so there's lots of high grade coins. And those that weren't saved REALLY circulated so there's lots of low grade coins. The middle grades (F/VF/XF) are difficult to find because there aren't many. Mine is a F-12
And/or "average" collectors that can afford to get a middle grade (F/VF/XF) example hold onto them longer and therefore they don't get onto the marketplace as often as low or high grade ones. Low grade ones likely get upgraded more often. The high grade ones likely are bought by "investor" collectors and get "flipped" more often. Once I can save up I intend to get a 16-D in Fine and hold onto it for a long time.