Haha. Depends on the intent of the design mostly. You generally shrink eyes to make characters appear older or more mature. Big eyes and forehead are more reserved for a character you want to seem precocious or “cute” (like Xrd May or an Elphelt). From some new interview that was floating around it seems the title isn’t that much later than Xrd, and the devs were saying they were more just “growing up” the designs.
To me, it seems they’re trying to generally round out the characters’ features, with faces/eyes/mouths incorporating more curves than the sharp lines used heavily in Xrd. May in particular reminds me more of a Hayao Miyazaki character design, where (human) characters usually have rounder and less exaggerated facial features (compared to modern anime which tends toward more angular designs). It’ll be interesting to see how cohesive this stylistic change is across the cast.