Hi Nick, first impressions; it's dark, gloomy, dull.
That alone would be enough for me to go onto the next site, however;
1. The buttons at the bottom are nice, once you realise they are buttons. Too dark to start and can't read the text underneath.
2. Your e-mail link (top left) does not do anything when I click on it.
3. Your 5 links top right do nothing when I click them.
4. Since when has 'web design' been one word?
5. It's depressing me looking at it, it is so dark!
Ask again when it is a bit more cheerful, lively, vibrant and generally more appealing!
I will just add though, that in terms of structure, it is fine, with different colours it would be great
With respect to SEO, there would be so much work involved in getting good ranking for your business area it is almost not worth the effort. The time could be better spend contacting local businesses to get work.