You should have arbitrary effects as a chaotic and random effect. When a price control effect occurs arbitrarily. This makes the market not an organic entity, but a regulated one.   Someone or several people decide to take action to control prices. Especially the so-called trade war.   In 301 AD, Diocletian promulgated the Edictum de pretiis rerum venalium, known as the Edict on Maximum Prices. The state set limits on a huge amount of goods and services, in response to inflation and prices that the government considered excessive. The preamble itself accuses merchants of raising prices even when there was plenty.

A quick preview of retail sales and statistics VM_Preview1.mp4    

Quite interesting, some things are similar to my upcoming Market suggestion, for example: -Selling resources at retail (slow, but more profitable than direct barter): I thought of local trade (retail) represented by a trickle, while global trade as it is now, but more profitable, while removing instantaneous barter and integrate it on the mentioned ideas (I think it's a silly system copied from AoE that many other games don't have). -Once units appear on the map, they consume coins and food: I like the upkeep idea, but it's more radical, for now. -If a player's balance of these resources becomes negative, unit recruitment and construction are locked: I think it's not enough punishment, makes sense for a certain time, but after that, units disbanding and mercenaries rebelling by going to Gaia would be interesting. -Interest on deposits: nice idea, since "there is evidence for the existence of private banks in Greek antiquity since the end of the 5th century BC. They functioned as offices for changing money or keeping coins and valuables. In addition, they operated as pawnshops", from the Museum of the Bank of Greece. -Traders. The main role is to influence prices during barter transactions. The option to generate resources by moving between markets has been disabled: that's where I'll propose things in the exact opposite way (Traders travelling and doing the bartering trades continuously).

yes, but this is already the case with elephants. IMO the target should be to keep their maneuverability through buildings and other immovable obstacles as close to current as possible.

UPDATE: Version 0.12.1 Added Wiki button Each game will start in a random month