I got a the same brick after installing IOS35 from Punchout. Punchout wouldn't play without a "system update", so I ripped all the update files from the disc and applied them one-by-one in wad manager, since I wanted to install only the minimum to get Punchout working. Well, it turned out either the IOS35 from Punchout was bad, or there was a bad interaction with the files I have from cIOS, because after installing that one I got a hang when attempting to return to the Wii System menu, and now the Wii won't display anything when powered on.
I tried SaveMii with the Punchout disc in (and with the Smash Bros Brawl disc), and neither had any result.
Here's a question: If I send this back to Nintendo to repair, is the charge $75 for in-warranty repairs, or out-of-warranty repairs? If it's for in-warranty, then isn't the Wii no longer in warranty because of the homebrew stuff? If I send the Wii back to Nintendo to fix and the find out it's out of warranty, will they simply hijack my Wii?
EDIT: Typo fix