More important than your specific file comp, your in game decision making is probably most important. As a small example, one time I was playing WK verse this Urgrant player. So I knew he was going to open Cath. To beat him, I opened owl sage - owl sage and it pretty much gives me a massive advantage early because I can backlash the opponent's owl and also carry the threat of tidaling his Cath.
For your Gowen file, a big determinant of your success is going to be how quickly/slowly you trigger your souls, when you work in your salamanders, and how you manage your SP.
BTW if you're looking for a good tech card, I'd really recommend a single or two copies of Mage Pixy. It can really help you out verse most meta files.
The True Hero / Callonia