Welcome James,
Good points are.....
You have a certain style, using grunge style text is very modern by you haven't overdone it by filling the background with it, so you get a nice clean finished effect.
I like the change in colours on certain pages it separates the different sections.
The main nav is great for me, it's clear, along the top and takes you to the sections you want. The internal nav can be a bit confusing, I was enjoying your logo work then when I came to last one I wasn't really sure what to click to go next?
For your first site it's good, but it's what I call a designers site, now you've got to learn a little bit from the web developers handbook on useability and Search Engine Optimization to really make an impact.
Read some articles on CSS and start by trying to build text based content in. The page really needs to be centred and there's no reason why you can't fill the page, use the space well.
Also look into various interactive portfolio options.....
Great work, bad portfolio.....
Graphic Design Portfolio / Branding / Logo Design / Nottingham
Way too much scrolling.
Flash Portfolio...
Nate Smith :: Graphic Design Portfolio
Nice for users not so great for search engines (although not completely)
Lightbox style....
www.fergalkeane.com - graphic design portfolio for fergal keane - ireland
Great for users, can be all localized on one page and good for search engines.
An alternative to lightbox.....
Web Design Portfolio UK
As above.
Using sliced images....
Graphic Design Portfolio
Slow, not in much order and poor for search engines.
All have pros and cons, pick what's good for you and have a play.
Good luck with the site, hope this helps.