I've seen the boob plate in play for a lot of videogames and some anime. I've also seen male armor that simulates the pectoral and abdominals. As a personal preference, I find these to be more appropriately human. Flat armor is fine if you're trying to intimate your foe into thinking you're some kind of demonic ROBOT. But usually, these games don't play that way.

Specifically to Jessie, I don't find her armor weird-looking. Honestly, I question Biggs, Wedge, and Tifa not wearing armor. Even Barret wore some kind of steel cummerbund in the original.