It's now possible to start the Wii U Homebrew Channel / Launcher from the Homescreen, thanks to the recently released Haxchi hack by well know 3DS / Wii U hacker smealum.
Interested? if so we've put together a easy to follow tutorial that will take you though the process from start to finish.
The tutorial will teach you how to install a permanent Homebrew Channel icon on your 5.5.1 Wii U. The end result will be you can load the Homebrew Launcher from the Wii U’s home screen, just like any other app or game. The Homebrew Launcher will load first time, every time, unlike the unreliable web browser exploit we have had to use until now.
View: Wii U Permanent Homebrew Channel / Launcher Tutorial
Note: Updated 1st December 2016 with a much easier tutorial, linked to above.