Foreign traders would flock to Scottish ports, you're right, but at the expense of your local markets. Local craftsmen and merchants would become dissatisfied with the competition and your high taxes. At the end of the day the economy would suffer.
Grant certain burghs the right to trade. Only these burghs can hold markets and sell goods.
Advertise your goods throughout Europe. Good advertising is a must for a flourishing economy. Then just sit back and wait for the traders to flock to Scottish shores.
Which card are you going to play?
