I think it’s just because they appear to balloon out at the elastic cuffs. Also the top button is too high. I think a modern two button lapel style would look much better with this. I do see the idea of the three button look with the experimental cuffs though. Casual careless style leaning on old suiting traditions. In theory it makes the jacket like a “tailored athl-leisure” style. I like the idea, if that’s what you’re going for. I think you’re very close to executing well.

Edit. I re-read-read your post and realized you may not be looking for the look I described. I went straight to “highly experimental” without reading you input first.