CE price is directly influenced by what people think the price of CE should be. Meaning what people will pay and what people will sell it for will be what the price is. Someone putting up x20 CE for a certain price has very little effect on the general consensus of CE price. Everyone willing to buy or sell CE for 4k crowns on the other hand, has a major affect on it.

For people to hold it at a price like you say, everyone would need to commit to that price, either consciously or not. AKA no one posting drastically higher or lower prices to what it is. People who buy and sell CE are often far too eager to do so to wait out price changes so they often post slightly higher selling prices than the last price sold and slightly lower buying prices than the last price sold, so you don't see much movement from time to time and these ups and downs are usually only a few hundred Crowns.

limiting CE amount would just cause people to sell more often with smaller amounts at the same price they are selling the 20 or 40 or however many more.

So when you are flipping burgers at your local McDonalds, and they speculate a rush of 100 burgers....does your manager limit you to sell only 10 per day?

This suggestion is a joke, if people are willing to buy a block of CE (or crowns) at a specific price, what's the problem? If the market is heading down (or up), then those blocks will be eaten away at in no time. If you don't like how a stock market works....then stick with the "trade" tab.