Early on, I was doubling up on coins in case gold went up. The idea was to sell off the dupes to keep up with the new issues. I've heard other say they're going to just do the Proofs (or Uncs) and sell off the others. This intermediate selling will keep prices down for some time to come.
FS coins sold by the Mint sell at about a 20%-25% premium over bullion. There are times when I've found NGC/PCGS graded coins (MS70/PF70) on eBay for less than the Mint premium price...which is a "no brainer". However, every FS coin I buy on eBay is one less coin I can afford to buy from the mint.
When the newer commemoratives come out, it will be easier for most folks to buy a "one-and-done" coin rather than trying to keep up with a series that has five (5) more year to go!
I wouldn't be surprised to see some of the more obscure future issues sell less than 2,000 Uncs. That likely wouldn't happen unless the coin prices go over $1000 each...that would be gold around $1600/oz. If gold goes that high, I'll probably have other, more pressing issues to deal with than my coin collection.