In an attempt to be brutally honest, you need to start over on this concept. I'm not sure what the company is, so I can't really give you any direction to go. This screams of a late 80's logo and isn't very memorable.
maybe you should try to work on the text first, get ideas from logos in the net and start from there...be inspired.
before you start, just have a look on some interesting logo references like http://logopond.com
This logo cannot be used on several media because there is too much detail in the towers and you use gradients.
a city doesn't stop suddenly on the left and right. You as a designer should work this out differently. The font doesn't fit either.
But i can see that the company is located in london(?) Have you thought about why you want to express this so badly? maybe you should approach your company from a whole different angle.
Like Dan Allen says: Get inspired :)
To much going on. At least try to have content contained. Simplify with less complicated element.