I think the major issue with any console being hacked, is that 99.999999% of the time, it is done in order to exploit and perform tasks it wasn't intended to mainly in order to play pirated games and software.
If the main focus to Homebrew and hacking was to IMPROVE the current consoles interface and experience, then I think the involvement and the creations would be more robust and interesting. Meaning, there are many Wii and Wii U things that are annoying or redundant, like all the Warnings about the fact your console was on for 5 hours or something. Constantly having to touch the OK button to acknowledge things. Also, although you can "backup" your settings and your games and your saves....then what? Once again, the reason for most backups is not to help the user DO something, but more incase the user screwed something up.
If someone built a STABLE and robust interface for the Wii U that actually performed useful tasks, there would be no reason to abandon the efforts. For instance, at this point in the game there should be consistently stable apps that work every time for everyone. This is not a PC, so there is very little discrepancies between each unit. Having a Wii U "OS" that allows for full graphically interactions with useful tasks like clearly and easily accessing ALL saved data from any source, clearly seeing it, exposing it, giving options to manipulate it and then USE the actual data in a DEFAULT manner, not CUSTOM, the customizing is what kills things.
I should be able to insert any Wii, Wii U (or GameCube on a Wii) disc, upon loading the OS should give me options to Play, Copy, Select which Save Data to use, which Mii to use, etc. Amiibo support for and discovery, making the NAND cleanly and neatly accessible to work with the OS and apps.
I own 2 Wii Us and 3 Wiis, all since release and launch. I've hacked them since forever and have updated and moved along with each year of progress. I can safely say that to this date, there's really NO POINT in hacking any Nintendo console for any reason, unless you are playing illegally. Cause all the real world legal apps and exploits don't really do anything of any actual use and work consistently.
I would like to see an combined effort among coders to create ONE really great Wii U "OS" that does everything we want it to do "NATIVELY".
Whether you are doing it legal or not, I think the main goal would be to have a Wii U that functioned like it hasn't been hacked and performs all the functions it SHOULD have performed out of the box. That means easily and simply loading / launching any and all GameCube, Wii and Wii U titles and VC titles from an external USB HD using your saves and your Mii's and your Discs. Leave everything else alone. Focus on making these tasks perform perfectly every time.
I am not a programmer or coder, but I am degree-holding artist and graphic designer, I am a teacher as well and I have built way too many web sites over the years to count. Including way back to fully develop Macromedia Flash sites, early CSS, HTML, PHP and some other basic web stuff. I am way more than willing to help out or contribute to anyone's builds.
I think the USB Loader and WiiFlow combined with the SaveWii apps and such, are at least in the ballpark of the right direction, but they've all been too buggy and incompatible and overly complicated when it comes to installing and configuring. So maybe trying to mash these apps together along with a few other's might be a good starting point? WIth the new Tiramisu hack hopefully someone is getting closer to truly taking over the Wii U OS.