• It's necessary that your site directly gives information regarding its services and products which keeps visitors on your website.
• Use Bullets, headers and sub headers to highlight your content. This helps visitors to find the data which they are looking for.
• Try to avoid fancy and tiny fonts for website it may attract visitors but not easily readable by them and you lose them.
• If it's not necessary than don't require registration and don't force visitors to do registration and submit some other information like email id, etc.
• Don't overuse flash for your website which decreases your website loading time. And if you are using an audio file then allow people to play it themselves.
• Don't forget to give your contact details on your website by which people contact you and you can also get important feedback from your visitors.
• Avoid to use HTML tables in your web design instead it use CSS because it's faster and more consistent.

Hello...
web design mistakes that we could make while designing a web site are:-
1)Not Changing the Color of Visited Links.
2)Non-Scannable Text.
3)Fixed Font Size.
4)Page Titles With Low Search Engine Visibility.
5)Anything That Looks Like an Advertisement.
Thnx...

No question about what you said, but do you think it is enough!
    The trend has changed a lot these things are based on visibility, but when you talk about usability and taste of people or based on current trend (You know web is growing it is the phase of being mature). You can check following check points:
What a user experiences on your site: Is it giving them feel of breezy, hassle free browsing i.e check whether you have removed all the  complexity or not!
Perceptibility : Is it interesting,  can people memories, contextualize, visualize or some need to rinse and like to repeat?
Simple and Intutive : At most of time i have experienced in the process of value addition we usually do complexity additions.
Have We Checked who are our audience?
Is it satisfying the sentence 1 Web for all

I have learned much on typography since, and continue to learn more about the complex world of web typography.

The Web Designing is a foundation for any website,
Use minimal graphics to speed up the website,
Use high quality images,
use light colors,
good content fonts,