Polos aren't really aimed at girls, and even then that shouldn't be a priority at your age.
The later Rovers aren't actually bad cars, they just had an image of being for the older driver. That doesn't mean they were unreliable, or badly made, just that they didn't have fancy bits of plastic that appeal to the shallower, younger driver.
Now you're seeing sense regarding drivetrain layout and car marque, you have to forget about the image or the intended market gender, and go for something that's cheap, safe(ish), reliable and not too depressingly slow.