>>1474689The idea that step-thru frames are "women's bikes" is one that has survived from the 1890's when women were expected to wear very long skirts, which made getting on a diamond frame impractical. Step-thru frames were (and usually still are) heavier and not as stiff as a diamond frame, which is why they have never been popular for men, and also why bloomers were invented.
>>1474791Your old front derailer will still work fine as long as you have the same sized chainrings on your new crankset (assuming you're replacing that) as the old one.