Julio Potier

This plugin adds 4 more colors into your admin/member profile. It changes the “4 squares preview” with a beautiful gradient preview. You can click on it to select the teme : it changes in real time to preview colors ! 
I added 4 icon themes for your admin menus, same behavior : click on it to preview.

BAW Better Admin Color Themes

Add more color themes and icons into your admin dashboard ! You can preview theme just clicking on it (JS required).

WordPress Monsters

It’s a great admin color theme! If you spend a lot of time with WordPress admin panel, this is the best way to make it beautiful and productive. Do you suffer from sore eyes? Try to use our admin theme! This color scheme has specific design that will help you to concentrate on your work for a long time without any discomfort.
This plugin provides:
<ul>
<li>Beautiful and relaxing color scheme</li>
<li>Customizable admin background</li>
<li>Possibility to add your own logo in admin panel</li>
<li>Easy to use and simple to config</li>
</ul>

Eye-candy theme by WordPress Monsters

Add new admin theme to your website. If default admin themes irritate you and you suffer from sore eyes, this color scheme is the best choice for you!

BAW Better Admin Color Themes vs Eye-candy theme by WordPress Monsters