From a discussion from Ares Global-1 yesterday, many of the long term players supported the idea that the ratio of gold coins to gems has been increasing. This is raising the cost of gem buildings, with a spot check for noble residences ranging from 750-850 gold coins (95 gems) and the improved silo for 15,000-17,000 gold coins (1995 gems), giving an approximate ratio of 7.5-8.5 gold coins to gem. From personal recollection, I bought my initial noble residences at 250-300 gold coins over a year and a half ago, which would suggest that the coin to gem ratio has tripled in that time. Higher end resources seem to follow a similar pattern, as the cost of granite has doubled on Ares over the same time. Because of these cost increases, lower level players will have a much more difficult time in getting past the times when island growth is required in order to progress in the game. The most likely reason for this shift is the steadily increasing total gold in game and the free market restrictions build into the trading system.
First, as the number of players on each server both increase in number and the number of higher level players increase as well, there is an increasing total capacity to make gold. At the most basic level, each player who logs in for a week gets a small gift of gold. I would also venture that the majority of players who were in game last Xmas received a gold tower, which under normal conditions provides about 4 golds/hour or 100 gold/day. A single level 5 gold coinage will produce about 290 gold per day, unbuffed; at the more typical minimum of triple buffed, it goes to 870 gold/day, each. While there is a cost associated with creation of the gold chain, it is a capital cost only and the only running cost are the buffs and gold ore or deposit, which is also generally obtainable from adventures without removing any gold from the game as a whole.
On the other side, there are very few gold sinks in the game. The largest gold sink is seen in the building upgrades. While some of these numbers are a high cost for the level of the player, the amount is still a capital cost and ultimately is much lower than even a single days production for higher levels, who have passed that point already. There are a few smaller constant gold costs; for instance, creating manuscripts and sending explorers for adventure searches. There is also some gold lost in the trade office, for people who wish to post multiple trade offers. The actual trades, however, do not remove any gold from the game; it simply transfers it from one player to another. This lack of gold sinks in game makes it different from every other resource in the game, as those resources are consumed in play, one way or another - only gold tends to remain in game indefinitely. The loot spot market may contribute to some of the issue, as it requires a large amount of liquidity for the sales.
The trade office system also tends to favor increasing prices, as it prevents the density of sales needed to promote a true free market. The limited slots per item is one factor in preventing a higher density, as few would use gems for low profit sales. The increasing cost for placing additional sales requires the seller to either accept a lower price, or raise the price to compensate for the loss. Generally, the lower density in the market prevents the competition needed to lower prices.
Looking at the problem, there is no clear solution that is fair to the players. The key to fixing the problem is to reduce the total number of coins in economy, but focusing on the higher levels where coin is more abundant already. A similar problem is seen with guild coins, which despite a real cost in obtaining, have a relatively low value for the simple reason that there is very little of value that can be bought using them. While one potential solution is to have an actual game gold merchant, it would be important not to have normal resources available there, as it would then create a price cap for the player trade office. One thing that may be a good sale item are the number of decorations that have already been created that do not affect the island economies nor are something that would be desirable as a gem purchase. However, if this question is not addressed, prices will continue to increase, resulting in the large gold hoards already in game continuing to lose their value, and making the game increasingly difficult for the gold poorer players.