Well, let's see how long this takes; I am going to address as many points as I can, so this post might be on the longish side... Anyway, it gives me great pleasure to partake in this discussion - this is what I had hoped the VSL forum would be about in the beginning (save for technical issues). So, thank you everyone for the kind words, and in no particular order:
Anand: Arnold Schoenberg (1874-1951). Lest we forget that we are discussing Schoenberg's pre-dodecaphonic position in compositional hierarchy. His contemporaries then would roughly (±15 years) include: Claude Debussy, Maurice Ravel, Richard Strauss, Igor Stravinsky, Bela Bartok, Gustav Mahler, Max Reger, Alexandre Skryabin, Sergei Rachmaninov, Jean Sibelius, Gustav Holst, Francis Poulenc, Giacomo Puccini, Alexandre Glazunov, Rheinhold Gliere, Ottorino Respighi, Manuel de Falla, Edward Elgar, Florent Schmitt, Franz Schmidt, Carl Nielsen, George Enescu, Charles Ives, and many others - probably important - that I am forgetting in haste...
Verklarte Nacht: This work was premiered in 1902 (having been finished roughly a couple of years earlier). Let's examine musical premieres around that date (±2 years): The Dream of Gerontius, Symphony no.4 (Mahler), Piano Concerto no.2 (Rachmaninov), Pelleas and Melisande - Estampes - La Mer..., Romanian Rhapsodies, The Divine Poem - Etudes - Piano Sonata no.4 (Skryabin), Ein Heldenleben (composed almost concurrently), Jeux d'Eau - String Quartet in F (Ravel), Symphonies nos. 1,2 - En Saga - Finlandia (Sibelius), etc. There was apparently such a fuss about an unresolved 9th chord regarding V.N. (boo-hoo), when I think of, say Ives' Scherzo for String Quartet, it really makes me laugh... And what was that review? "Half Wagner, half Brahms, half Strauss, and no Schoenberg". I respect, but actually feel neither hot or cold for the work.
At any rate, I am not saying that anybody here claimed Schoenberg to be top shelf, but rather protesting my rating him so low. I actually take my cue from R. Strauss who considered himself a 1st class 2nd-rate composer, and go from there. Schoenberg as a tonal composer -including Gurre-Lieder, the chamber symphonies and what have you- is maybe one or two or three places from the bottom and on par with some on the above list (for my taste), and since that list does not contain titans such as Chopin, Brahms, Verdi, Schubert, let alone gods like Wagner, Beethoven, Mozart and Bach, bottom 3rd rung is my best concession. He was a great teacher of course and an extraordinary mind; his textbooks and collected writings make for very interesting reads.
There are three main reasons why classical music is dying: a) It is not culture that one can acquire in adulthood, when striking it rich for example and wishes to fit in with the bourgeois crowd. Art is easy; you see a splash of shyt on the wall for three seconds, and pretend to appreciate it. You don't have to endure two hours of silence in a concert hall listening to stuff to which you cannot relate. Children today are not flooded with great music enough at school or -more importantly- at home, in order for their ears to acclimatise, thus acquiring that culture, b) It is now a more than less museum culture, rather than a vibrant, living culture (like pop music), since composers who could be great tonal ones, either followed academia, or became film composers (a very different kind of music) or pop/rock composers, leaving lesser personalities to carry the banner, c) Technology has replaced the need for families to make their own music by themselves, for almost a century now. Let's all get glued to the TVs and iPads.
John Williams has released a great CD with music for cello and orchestra (the concerto you mention included). It is polished, pleasant music, for more than one hearing (and that is saying something). As far as labeling this music, it is simply called 'lightly chromatic'.
An interesting point is that you consider Williams a melodist, when in fact his inability to compose a melody is his one Achilles' heel. Williams composes 'themes', mostly chord-based and, by his own admission, he has enormous trouble coming up with those too... His music sounds melodious, but isn't really. He just knows his craft backwards and his other skills are so well developed, that he furnishes us with such great stuff. His one "melody" that everybody seems to melt over, is so uninspired really... A series of quavers so forced and contrived, but so well presented that (other) people swoon to their sound.
Mike: You know that you and I come from the same kind of background, so when you mention Gurre-Lieder and Verklarte Nacht not being 3rd-4th rate music, you do add the expression "from a technical point at least", knowing that I cannot disagree there. I also agree with you that today's top composers' technique is at least as sophisticated as that of the masters. The same (and more) goes for the instrumentalists of today. So it is puzzling why we don't have any Richters, Casals', Heifetzs, and Furtwanglers today, the same as we don't have Prokofievs. Well, maybe not so puzzling...
fahl: Shoenberg's late-romantic status is something of a post-mortem myth. Even he was disgusted in his own Gurre-Lieder after a few years (although I find many useful things in there, and orchestrally consider it more advanced than Mahler). Mahler's defence of Schoenberg may have had something to do with wishing to help his kindred, as with anything else. And how many really were the late-Romantics? With Wagner's, Brahms', Bruckner's, and Tchaikovsky's demises, who is left really? Mahler and Strauss are clearly his superiors, so it isn't that he has great competition... Reger, Schmidt, Nielsen, Stenhammar and a couple of others?
Your asking me about other tonal composers of the 20th century gives me an opportunity to state that I didn't enter this 'spat' -as Mike I think put it- between tonality vs. atonality. I just jumped in to correct some historically incorrect assertions, as I saw them. Like I said in my post, I appreciate many works by atonalists. For example, when I first heard Ligeti's Requiem (and I remember being intimidated as a student by the A3 and a half long score), my jaws dropped. Having heard so many other such works from the canon, from the off this work grabbed me by the spine. For once, I felt like I was in a cemetery and the dead were chanting from their graves. Tonality or atonality, when a work has such an effect on you there must be something to it. By the same token, I am not that crazy about the metronomes... I have great respect for George Crumb's mysticism and soundscapes, but amongst atonalists these are the lightweights (compared say to Ferneyhough, Stockhausen, or Lachenmann). I envy Xenakis' power and objectivity. To me, his best works are like cosmic rays hitting our planet, like gamma rays do.
Tonalists: There were so many beautiful tonal to chromatic composers last century, where does one begin? Certainly Honegger (who has written a great book about being a composer - I recommend people read it, along with Hindemith's own, and Constant Lambert's Music Ho! before all others!), everyone I mentioned above, the obvious ones (Prokofiev and such), and then Delius sure, Britten, Tippett, Milhaud, Copland, Gershwin (the orchestral works), Martinu, Moeran (wonderful music guys, look him up), Villa-Lobos, Szymanowcki, Schnittke, L. Boulanger, Hovhaness, Cowell, I am going to stop here as I realize the catalogue would number many tens of composers, including many you've never heard of that I wish you had, but I can't omit Barber, Lutoslawcki, and Rautavaara. It is interesting you mentioning van Dieren; I have respect but no particular love. He is certainly in the list even though I've only heard a couple of works.
William: I have great admiration for Varese, and I believe I own his complete works and most scores. Powerful music and concept!
Finally: Please understand everybody that music for film is not the same as concert music, unless the composer is able to produce both kinds ( ex. Korngold, Herrmann, Williams). The aesthetics and requirements almost could not be more different. The fact that both musics are composed for orchestra means little. It is the same as comparing Pink Floyd to Bieber as drum kits and electric guitars are involved in both cases.
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