Not to mention the 23 1/2 minute Side B opus "Echoes" that obviously inspired both Dark Side and Wish You Were Here. Both of those albums grew out of Meddle.
Floyd is an interesting band because they evolved so much from their first to last album. They span numerous genres because of this, thus they have numerous 'greatest', depending on an individuals taste.
Regarding Meddle, yes, great album. However, I think the Live at Pompeii version of Echoes is better than the studio version. You can also see recordings of Dark Side of the Moon on the Live at Pompeii video.
To say that Dark Side and WYWH grew out of Meddle is a bit of a stretch. Floyd calmed down a lot after Meddle, I would even venture to say that Dark Side is a mix of styles that are shown in Meddle and Obscured by Clouds (which is very calm 'experimental' wise).
------- Post Edit -----------
Floyd calmed down until Waters totally took over with The Wall, then they became just insane (perhaps reflecting Waters' state of mind?!?)
But "Fearless" alone highlights a Pink Floyd at the height of their experimental days before the string of concept albums.
I'm curious by your use of the word experimental in this context. Because when I think of Floyd's experimental side, I think of albums like Atom Heart Mother or Ummagumma, more psychedelic like. This is when they really started experimenting with their instruments, and Roger Waters with his synthesizer.
It seems to me like Meddle is a mix of mainstream songs and experimental songs. Fearless and San Tropez being more mainstream and Pillow of Winds, Echoes, and One of These Days being more experimental.
I also think that Floyd revolutionized the music industry with Dark Side of the Moon because the album didn't comprise singles, it was an album that told a story from start to finish. It even has a beginning, middle, and end. (The climax being Any Colour You Like)
Oh yeah, did I mention that I'm a Floyd Head?