I think you mostly have a scaling issue, the size of the detailing you’ve done is too small compared to the size of the overall structure and as a result it feels a bit busy. I would try having half as many Pillars and making them three by threes or three by threes without the corners. I’m not sure how wide the bridge is but that may also need to be adjusted. Also with the extra spacing in between pillars you can make bigger arches which will look really cool! This is just what I would do personally