I come to the same conclusions about adequate pirating demands, but I differ on the reasoning.
Realistically, pirates may have an inflated view of how much traders make. If you've ever encountered beggars in a developing nation, they are as likely to request an obscene amount of money as a small one. They just know that tourists are much richer than them, they don't know by how much.
If pirates are more sophisticated than beggars, they may have a very good idea of how much traders will pay. In that case, the market will set the price. The pirates demand will meet the traders supply and there you go. Don't expect a solid figure to bank on though, since different traders will value that money differently.
In terms of fun, getting pirated the exact amount you can "afford" to lose can stink. I don't want to lose my profit or more for a single run. If it is a long run I don't want to lose any more than half of my profit. I am playing this for fun, I have limited time, and the small satisfaction of a good pirating RP experience does not add up to 20 minutes lost. In the face of high demands, I am more likely to fight to the death than pay up. Fighting is fun, it's a big universe, I work for Interspace which conceivably would set such a corporate policy (especially since they don't compensate me personally when I am pirated on company business), and perhaps the pirate won't bother with a ridiculous demand next time.
