[Jeir]

Looking at pic 2, Chubbs may indeed be female. =D
Is the wheel at least 11inch/28cm in diameter? That's generally the smallest a syrian should be given, and if Chubbs is indeed female, there's a chance she may need a 12inch wheel, as females can often end up bigger than males. But 11inch is usually good enough.
As for the balls, please avoid them. Hamsters are almost blind (colour blind, and can see clearly maybe 2inches in front of their faces), and the balls are actually terrifying for them. They can't see where they're going, they can't feel anything with their whiskers inside the ball, so every time they knock into something, or worse, fall down something, is just scary/dangerous.