Songs that Epitomize Each Sub-genre

If Neo Prog style didn't start with Merillion's Script for a Jester's Tear the album (1983), then One for the Vine is a great example of Neo Prog song recorded in seventies.
In fact, BrufordFreak asks not for the champion bands of the PA genres, but for the songs that will best represent the genres at his radio show. So, for example, I could put on my list Genesis' The Knife  as heavy prog song  instead of Uriah Heep Salisbury and to not make a mistake at all; it's a same thing with One for the Vine as Neo Prog song as well.

The solution is album-tagging and multi-tagging. This way we could document the various styles that a band covered in their lifetime and categorise their albums to more helpfully to anyone one interested in a particular sound. It must be emphasised that once you hear an album for yourself any prior categorisation of that album becomes essentially meaningless, it is merely a guide for those who haven't heard it. Categorising bands is an exercise in futility because bands have an annoying habit of deliberately defying convention.

None of the early Neo Prog bands thought they were creating a new subgenre of Progressive Rock music and I would be very surprised if any of them considered themselves or the albums they recorded to be neo anything at the time. They were young Prog bands continuing the established genre and the Neo Prog tag is something that was applied to them retrospectively. They certainly were not new-wave bands trying to play Progressive Rock - some of these bands, while not securing a recording contract until the early 80s, had their origins in the late 70s - simply listening to the early (demo & tape) recordings of Twelfth Night reveals no "new-wave" influence or stylings.

Dean wrote:  reading the OP is informative to say the least, it didn't ask for examples of Neo Prog.   (You noticed. . . ) I've got my own ideas about how to approach retro- and neo-prog. Avant/RIO ... Slapp Happy & Henry Cow - Riding Tigers was thinking Henry Cow or The Mothers Crossover ... Moody Blues - The Story In Your Eyes Nice one! Moodies, Family, Supertramp, even PG's first solo album all work for me Canterbury ... Egg - Seven Is A Jolly Good Time Yes! I was leaning toward Egg, too, I don't know why. Kind of 'mature' but still fun Robert Wyatt Eclectic ... Van der Graaf Generator - Man Erg Was listening to Pawn Hearts and Godbluff all night last night. Tough to nock out Starless, though. Depends if I decide time is a factor. Electronic ... Tangerine Dream - Ricochet, Part One Again, not sure how much time I want to give to "the old stuff"--aside from introducing the sub-genre. Heavy Prog ... Babe Ruth - The Mexican What?!?!? Another new one?!!! Jazz Rock ... Mahavishnu Orchestra - Thousand Island Park Think I might go with one of Cobham's but MO is definitely in the conversation! Jazz Fusion ... pass Is that Joe Pass?  Am leaning to Herbie or Joe Henderson Mwandishi era. Krautrock ... Neu! - Negativeland Like the Neu! ideas. Can, too. Something shorter than Ash Ra or Amon D. Neo-medieval/Baroque Prog ... has to be Gryphon - Gulland Rock Awesome choice! I was perusing Mushrumps for just such a choice! Neoclasssical Prog ... The Enid - In The Region Of the Summer Stars (track) Cool! Had that one cued up, too! Prog Folk ... Tim Buckley - Phantasmagoria In Two Not sure if Tim is my choice to represent. So many to choose from! Psychedelia ... Kaleidoscope - In The Room Of Percussion (not really, it's just one of my favorites ) Never heard of them/it!! RPI ... Le Orme - Ritratto Di Un Mattino Le Orme over Banco, PFM, Museo, Osanna. Tough call but I'm leaning toward Raff's suggestion: "Dopo..." Space/Atmospheric ... Hawkwind - The Psychedelic Warlords (Disappear in Smoke) This may hurt, but, I haven't heard a Hawkwind song yet that engages me. More likely to go with Floyd or even TD/Klaus for this area. Symphonic ... Renaissance - Innocence Really!? I can think of a lot of Renaissance songs, but "Innocence"? Why? (I'll have to give it a closer listen later.) Zeuhl ... Magma - meh, no idea, pass No doubt in my mind: I've got "Hortz fur dëhn Stekëhn West" cued up for this one!

Avoiding the obvious choice of Kings and Queens really.  Nah, I just prefer Keith and Jane Relf's Renaissance over later incarnations of the band. But the album that Innocence comes from was the first full-blown symphonic album IMO, and the piano on that track is just sublime.

I would add "2112" by Rush and definitely "Stargazer" by Rainbow as sterling examples of templates for progressive metal.

Definitely a few mentions here that are more in line with my thinking. Before Rush 'took over' the sub-genre there were proto-Rush bands, nest-ce pas?