Well, most web designers will tell you to make your website more interactive and charge you exorbitant fee for creating Flash and AJAX scripts. But is that what your visitors want?
Is there any scientific evidence to back up any changes that will guarantee a better user experience?
Having a search engine friendly is not good enough. You need good web design to fortify your conversion rates.
Knowing how to SEO your web pages to rank high for your targeted keywords and not have a nice design, simple-to-use navigation and layout for your visitors may eventually drive away potential customers.