Jacket Shoulders

Hi! I recently bought an off-the-rack suit and had it tailored, the shoulders don’t fit perfectly, it doesn’t look big on me either, but I like my jackets to fit very close to my body. I didn’t even ask the tailor to fix the shoulders, because I heard that an attempt to correct them would affect the structure of the jacket. So, I work out and I’m trying to get a little bigger, I wonder if that jacket will fit me better if I get bigger shoulders. Thank you!