Check out Women in Love for a beautiful application of his tapped harmonics. Check out Cathedral for his experiments with the volume knob.
Check out Take your Whiskey Home for some nice bluesy acoustic guitar riffing.
Check out Spanish Fly for the VH style coming through nice and clear on acoustic.
Check out the cover of You're No Good for amazing applications of the whammy bar to make the guitar almost talk at points.
And lastly Check out Running with the Devil to realize that EVH was the FIRST guy to bring the loud, distorted, major third into hard rock---he did it by slightly detuning the g string to prevent the unpleasant buzzing sound. ((try tuning your guitar as normal, then kicking up the gain and volume, now play G major on the top four strings---it will sound like dog crap, guarenteed))
Check out Unchained for nothing short of amazing rhythm guitar while he is singing no less.
Long story, short? EVH covered a ton of ground with his new techniques and redefined electric guitar while doing so. These claims that he didn't 'say' or 'do' anything with his technique are just false--I'm sorry, they are. Jimi Hendrix brought the 7#9 chord to rock, was a really funky rhythm player and was insanely bombastic.
And also, there's nothing wrong with being 'commercial' as it were. That's actually very important, to me at least. It takes skill to digest the minutes of an underground style of music and keep true to the original style while making it accessible. If it was so easy to 'sell out' and 'go commercial' in bringing grunge to the masses---all those other bands besides Nirvana would have done it.
Most of the time, the underground stuff is not that good. For example, the Chemical Brothers techno versus most other techno.
Back In Black isn't a song. It's a divine call that gets channeled through five righteous dudes every thousand years or so. That's why dragons and sea monsters don't exist anymore.