Just have enough space and a good internet connection.
Thats about it, also using the nintendo update it patches stuff,
Even if you try prevent it.
Waninkokos just updates the stuff , leaves patches out.
If you have Waninkokos is more likely stuff will work, that updating and patching stuff with the official nintendo update.
Plus that patch4.0 thing has to be done after its in 4.0 I think, thats what i read since i don't use it i wouldn't know.
So you might want to find out more info about it before you do anything stupid
Like using the nintendo official update.
Plus if your wii bricks u can send it to nintendo and they can fix it for a small fee or none if you say that it was bricked while updating.