So I did look at coldboothax the last few days and now have the very first version of it ready using a new haxchi payload - CBHC (ColdBoot HaxChi)!
https://github.com/FIX94/haxchi/releases
Please ONLY INSTALL THIS if you already have the normal Haxchi installed and know that it works perfectly or else you will 100% end up in a dead wiiu, just install it over your existing installation and DO NOT INSTALL IT from a freshly downloaded, never started/tested game or you may brick. Also ONLY INSTALL THIS if the DS VC is BOUGHT ON THAT CONSOLE AND ON NAND.
After installing it you better go ahead and set up some DNS server protection, disable standby, NEVER touch the DS VC you used to install it again, so dont move it around on the home screen or settings or delete it and just generally be smart about it, I am not responsible for your dead wiiu because of user error.
Anyways, enough of that - what can this actually do?
It offers a basic menu from which you can boot into the system menu
which will get full signature and region patching, you can boot into the homebrew launcher and into a fw.img on your sd card which could be useful for rednand, also if you want to automatically go to any of these places just enable the autoboot option for it.
The menu controls are very simplistic, up/down to move the cursor and A to either select the option or change the autoboot option, you can control it using the gamepad or any wiimote, classic controller or wiiu pro controller OR if you are really desperate the the "sync" button on the console itself will work too - click once to move the cursor down and double click to simulate what A does normally.
Once autoboot is set up you can easily cancel it by pressing the home/sync button while the "Autobooting..." message is shown to get back into the little menu and go from there.