I'd like a feature which made it possible it send a captures trader back to one of your outposts with all goods the trader had, but it would cost you some amount of your crew which would sail the ship back to your outpost. Seeing as now you have the send your main ship to an outpost and then sail the trader back yourself. This would make it easier to catch traders but would still limit have many you can capture because after capturing a few traders and sending them back to port you would have to little crew to be able to operate your ship properly.