Jeez these designs are so bland, they look like something from an initial character draft. While their body designs are unique enough to be distinguished from the rest of the cast, the designs of their heads/faces are left wanting.
Topaz has a gung-ho military vibe but it's too muted. They should've been more creative with her hair, make it bigger and more trapezoidal. She's like Gile but without his recognizable flattop or Garnet without her square-fro.
For Aquamarine I say give her bangs with that short hair, deadpan eyes, or a cute button nose (optional). I know she has some sort of ribbon in her hair from the teasers, so make that more prominent as well. Since the show obviously takes some inspiration from anime, they should've made it show here.