Hello!
I don't think that a real "stress test" is possible for many players. Without a developed economy you can only trade a small part of all resources in the game. This will limit the number of resources per trade (leads to indirect problems) and the number of trades (less trades -> less realism of the stress test). Also the trade (and test) of event-specific resources is not possible.
The few number of resources leads to problems because you will fast run out of resources.
I think it would be better to seperate the tests for the new trading system and the new tutorial. The trading system needs much resources for everyone for a real test and the tutoral needs a good working trade system.