Hey, does the recent CD reissue on Zappa records sound better than the Rykodisc version? 

SteveG wrote: An entry level accessible Zappa  album or a jazz rock pioneer?

Both.

And therein lies much of its brilliance.  It is accessible Zappa.  It is accessible fusion.  It is intricate music, but you need not be a proghead or fusion freak to appreciate it.  It is one of those rare albums that spans both worlds.  Zappa could be a full blown esoteric, or he could make for a wider audience and he could do either exceptionally well.  

Same, and exactly. I also agree with whomever said it has some of his best guitar solos. Willie The Pimp!

I also feel it was early jazz rock at its finest.

The relationship between composition and improvisation is a fascinating aspect of Zappa's music. Some pieces are completely composed, sometimes he would improvise something and then turn that into a compositional element. One example being a solo in "Big Swifty" (I think that's the track - something from Waka/Jawaka) - Zappa improvised a solo, then the trumpet player notated it and overdubbed horns to play it in unison. Or "The Dangerous Kitchen" from The Man From Utopia, where Steve Vai transcribed a half-spoken/half-sung vocal piece (improvised?). Xenochrony is another example where he takes recorded improvisations and overlays them on each other. Maybe one way to look at it is manipulation of improvised material so that it becomes "composed" in a way - different than the "spontaneous improvisation" of Can for example. 

I personally think that Gumbo Variations is very improvised - not structured in the same way as "Peaches En Regalia" for example. "Son of Mr. Green Genes" is a great example of a combination of the two - composed piece with jamming solos in the middle, then back to the composition at the end - kind of standard in a way but nice - and kind of "jazz" in the sense of how traditional jazz pieces are often structured (head/improvised solos/head) even if it doesn't sound "jazz" in the sense of swing/instrumentation/etc.

Or as the master himself said - "Jazz isn't dead, it just smells funny!"

yes sir...  Willie the Pimp sits at #5 on my list of blow thy speaker songs ever...

Interesting insight about the relationship between "structured" and "composed" - maybe structure could be the variable on the continuum between composed & improvised. Completely composed versus completely free improv would be the extreme ends, with compositions that leave room for improv (blues, etc.) and more structured improv (traditional jazz) somewhere in the middle. 

Also wanted to add - Max Bennett, the bassist on all tracks on Hot Rats except Peaches En Regalia, passed away in September. I am a bassist and love his playing on this album. I started playing along with the album for the first time this past year (though I've been listening to it since the '80s) and the bass playing is really stellar. He was in the Wrecking Crew and played with LA Express, including on several Joni Mitchell albums.

Here are a couple of quotes:

On a musical blind date with Frank Zappa, Bennett was the principal bassist on the latter’s 1969 album Hot Rats. "I knew his name," Bennett recalled in 2007, “but not much else. The sessions went very well and he wanted me to join his band. I just couldn’t give up my studio work, though.” - https://jazztimes.com/news/bassist-max-bennett-dies-at-90/

Fans of more radical music may recognize him as the primary bassist on Frank Zappa’s classic Hot Rats album. 
“I was not familiar with Zappa’s music. Our paths never crossed,” Bennett told The Observer. “I was never a big fan of avant garde music in that sense. It was while I was working in the studio, what was it, 1967, I think? And I got a call from John Guerin. He said, ‘Get your stuff over to TTG’—that was in Hollywood—‘I got a double session for you with Frank Zappa.’ So we get there and we worked two double sessions for two nights. And that was the album, that was ‘Hot Rats.’” - http://jazznewsyoucanuse.com/2018/09/in-memoriam-max-bennett-2/

The first album by him (or the Mothers) that really stuck with me...we played this one constantly in college and usually when in an altered state.