Another way to look at the removal of the gold cap is player satisfaction. One of the biggest reason I kept hearing on the Freeport server for leaving was the gold cap. It's come up on forums for other MMO sites as well.
So what happens when you do, say, incremental gold cap per character unlockers? Let's say it's for 100p as someone suggested. We make it reasonable at 295sc to start which is well within range of what most players, regardless of means, can afford.
What is 100p? 100p is not much. Most Live players had thousands of platinum laying around. However, that free player is now a paying customer. That free player is now able to purchase things from you, the subscriber, off the broker and from the Auction chat. That player will also now tell his friends and family about this wonderful change to the game and those people are more likely to come here instead of to another F2P game that offers more variety and options for a F2P player.
So you end up with a happier player base, more paying customers, and potentially more staff to create more content.