I think you have darling legs, and I love that short skirt on you! I have a similar skirt - pleated and flirty, that I wear with fitted, high or boat-neck knit tops (and I always the bra straps so I don't look droopy with the high neck!), and ballet flats or my flat over-the-knee boots with tights. So I get to showcase my legs, without looking overtly, ahem, slutty.
I think a good rule of thumb is, if the legs are out, the bosoms are covered, and vice versa.
Your outfit in 3 & 4 are cute! - in my opinion - if you are going with a decidedly retro, pin-up girl look. You've got the curves and the attitude to pull it off! I can see that in your photos. But pin-up retro has to be a go-for-it look, not something halfway, otherwise it doesn't work. And you have to be comfortable with a lot of people looking at you, and women and men - especially men - complimenting you on the look. And your fella has to be comfortable with that, as well - otherwise you are going to feel uneasy.
I also think that at some point, you have to decide if you are enjoying the challenge of this shirt I certainly love seeing what you come up with! If you are having fun trying to come up with imaginative ways to style, keep going! But if you are feeling stressed, or like you 'have to' make this top work, then I must second Isis - resell the shirt. Put your effort and your money and your fun into styling stuff that you love