1. Get rid of family wealth/asking for money
2. The minority who exploit weighs more than the majority who don't? (Don't quote Captain Kirk to Spock!)
You might as well get rid of movement towards regions because some other family members might just fake it and not actually travel. Get rid of messaging because someone may tell a lie to another player.
Taking a loss on trading can be a powerful political tool, or even just good hearted realm love. Don't tell me that as Banker of the realm I can't spend my own coin to feed my own country because some schmuck may game the system.
Every change needs to be considered in terms of the potential and scale of possible abuse. Thats simply a reality of game development, otherwise you soon are only left with the minority that constitutes the abuses as all the regular players leave what they will refer to as a "broken" game. There is a good reason pretty much every game EULA talks about not abusing "exploits"
For similar reasons the maximum price is limited on the market.
