Sweatpant modification question

I've made several knit pj sets for my kids using the Schoolbus T and the Nature Walk pants or the Sandbox pants, but I thought I would use the Parachute Sweatpants this time. Because of the fabric pattern, however, I thought I would omit the side placket, and now I'm worried about my modification. I measured the placket piece (2 3/4"), tried to account for the seam allowance, then added 1 1/8" to both the front and the back pieces. But now it seems like it will be wonky! The back looks much bigger than the front. Should I try to make the two pieces more even? Thanks in advance for guidance! The forum is always so helpful for me :)