Another vote here for trying a longer stem

IMO, going with compact geometry is also on the right track. I'm no geometry expert, but I wonder if there might be similar bikes with an even more dramatic slope in the top tube (*not* a step through).

I'm quite a bit bigger than the OP, but personally, I've had good luck going with larger sizes and compact geometry; with a horizontal top tube, I usually have to size way down and then put on some kind of crazy long stem to be comfortable. My significant other's 56cm vintage Centurion is delightful once I'm on it- but there is no way to get a foot on the ground without injury.