The second one is an interesting angle. I think a little more of the road showing at the bottom would improve this. ( but only an amateur so just my opinion ;op) The first one could use some more contrast in the sky as it seems a little flat, but the angle of the bridge is great.
With the 1st i didnt want to do any burning in with the sky as i want the bridge to be the focal point, i dont think its flat by any means, not on my monitor anyway, but i see what your saying.
The second i took around 5 different compostions, there is a huge barrier type thing on the road which i found distracting so i went with this shot.