First off all layout :
- try aligning the site in the center so user off high resolutions
see the site in the center of their screen.
- I think their are also to many eyecatchers, so you don't know
where to look. I should try making the homepage a bit cleaner.
For the registration part :
- I'd put the cheapest package first and then the more expensive
packages. Most people when they see a price that's to expensive
they immediately close their window.
- Try to integrate the checkout page more in your site layout.
But offcourse it are just ideas
