Buzz launcher is great in that once you install and then download a theme its easy to modify backup and then upload if you want for others to use so its like open source. You can use the themes that others have created then modify to suit your self then upload your theme for other users to download and use on their phone. I switched from Go Launcher a while back to Buzz Launcher and find it very stable and fast.
https://play.google.com/store/apps/details?id=com.buzzpia.aq…
Themes ************ http://www.homepackbuzz.com/
Description
“Buzz Launcher” is a highly customizable launcher that enables you to apply shared Homescreens to your own smartphone. Buzz Launcher is an ad-free custom launcher that has more than 400,000+ free themes (the largest number of free themes among launchers)! Freely download, apply, customize, share, and even create Homescreens! (Available from Android 4.0.3+)
With Buzz Launcher, you can:
• Customize so much more than just your wallpaper or theme.
• Change between multiple smooth, fast, and easy Transition effects.
• View all Homepacks in a glance NOW: http://www.homepackbuzz.com
• Apply new home screens at a touch of a button, instantly!
• Personalize your homescreen with robust icon, wallpaper editing features
• Download and implement completely free homescreens within 5 seconds!
• Share home screens with a single touch via Facebook, Twitter, and Google+!
• Explore unique widget features such as clock, date, and battery
• Create your own customized widget using Buzz Custom Widget (Free)!
• Show your Homepacks to your friends
It drains your battery quite a bit, depending on what homepacks are installed. The more widgets you have the more processing power it requires.
I used it for a week then went back to Apex launcher for it's simplicity.