Sorry - my laptop pretended there were no replies between your cage photo and my reply, silly laptop!
The bottom pics are good - definitely girlies
Girls tend to be more difficult to keep in pairs so it's good that you're looking at other cages. Some very laid back boy pairs may be ok with shelves, but for girls I'd definitely recommend a cage like Soufflé posted. I personally wouldn't try and keep a pair of Chinese hamsters in a cage bigger than the one Souff showed (a rydon millhouse/mini duna/savic rody). You can pick up mini Dumas quite cheaply on ebay and the rody is now being sold again in pets at home under a different name. I'd take the shelf out of both if you get one with it included. Another option if you prefer barred cages is a mickey max cage which is a narrow barred cage of a similar size to the rody/millhouse. I've written some info on keeping Chinese hamsters in pairs which you can find
here. If you hear any squeaking or see any signs of injury or fur plucking I would suggest splitting your girls sooner rather than later - they can go from a slight squeak to significant injury with little warning.
Good luck with your Chineseys