Slits - or “does my bum look big in this?”

Putting on a snuggly cowl neck tunic length jumper today made me think - nay, wish - that designers and manufacturers would think of slits at hip level. These help a top, whether T shirt, jumper or jacket to continue past the hips or bottom in a straight A line instead of curving round the aforementioned fundament. It’s all very well covering the posterior but oh how much better for a top to skim straight past it.
Anybody agree with me? What modifications would you like to see designers implement?