brightonmike

Coffee Admin Theme gives the dashboard a bolder look with sumptous dark tones and a textured background. The theme is fully compatible with the latest version of WordPress supporting the new fly-out menus. Because of this, the theme will not work as intended in older versions.
The plugin has options to switch between different themes, and I will be adding more themes over time.
You also get a great selection of Google Web Fonts to choose, further enhancing your dashboard experience.

Coffee Admin Theme

Coffee Admin Theme is a WordPress dashboard plugin which adjusts the look and feel of the dashboard, via custom themes and fonts.

ryansommers

Slate provides a clean, simplified design for your WordPress Admin area.
Our goal was to simplify the visual design with a primary focus on the content writing experience.
If you like Slate, please consider leaving a review here on WordPress. Thank you!

Slate Admin Theme

This admin theme is particularly well thought for High resolution screens so it’s better than default theme.

Good

A clean, simplified WordPress Admin theme.

Coffee Admin Theme vs Slate Admin Theme