One of my Doc's Doctrine's regarding rock music is that, I believe, a band's first album is often their best stuff. Not always true, I know, but there's a preponderance of bands that produced killer first albums that were never matched after that.
My explanation for that? A band spends years usually playing together, trying to get that first record deal. When they finally score it, they record songs they've been working on for years. If it hits, the record company wants a follow up right quick.
With that point presented, I obviously like a lot of band's first albums. Van Halen's first was awesome. I loved their second about as much, and 5150, too, but that first album seems most genuine. Wish we could play all the songs on it (I did such on my Nightsides show at the Toledo classic rocker, 94.5, in the early 90's). Here's a video of a 14-year-old French girl, who goes by the Youtube handle of Tina S, absolutely mirroring Eddie Van Halen's "Eruption" solo of VH's debut album. Enjoy.