1. Dont cut off the legs.
Post is distracting, takes away from the couple. Try to keep backgrounds simple.
2. Better, but he is not sharp; she is. Color, "action" is pleasing. I think you either need to crop more from the left, or less. Back of his head is cut off.
3. Best. But I'd either include their full length or crop mid-thigh. Extraneous leaves far right. Shooting from further right down the length of the walk might have worked better.
I think that was not the best time of day to shoot. The sky is blown out. The faces are too flat for my taste. Also I have this feeling you're getting motion blur on #2, but it's too small to tell for sure. And you're getting some pretty wicked fringing on #3. Gotta work on your technique.
Say, did you take these with a point and shoot camera?
Apart from technical stuff... Call me conservative, but i'd love to see some open eyes on #1.
For #1) I think this shot should be done standing closer to the subjects and the rail, and with your lens almost parallel to the rail. Also might be nice to get that depth of field effect by using a larger Ap. and faster shutter.
Too many colors (red post takes away from subjects) and colors of light - maybe convert this to BW and crop?
Here's what I get from the one above but this will look better starting from your original because there is enough information to make a crop like this and still see some details.