This shows a lot of potential. I agree that perhaps there's too many skyscrapers, but perhaps as the city grows outwards it will look realistic for there to be that degree of upward development too. You could always describe the city as a long-standing commercial centre... though I agree that if you're going to have that many skyscrapers, having them ultra-modern in style might work better (Frankfurt is the obvious European example here).
The attention to detail in other areas, however, is certainly impressive. I love the opera house perching on the cliffs. This is definitely one to watch.