No doubt modding is steep learning curve. One has to limit change to one variable at a time, experience and/or research into particular parts sound qualities critical.
Listen, determine what you don't like about present sound, change out what you think is offending part with the chosen new part. Certainly, there is chance new part may not be to your liking, in which case you try another. I've had to go through this exact procedure any number of times over twenty year of modding. With experience these mistakes become much less common.
My present dac and custom built 300B monoblocks both use silver wired transformers.