The problem with music is that there's a lot of it. As the developed countries have increased in affluence, a broader and broader cross-section of the world's population has been able to gain access to musical training - meaning that more and more composers are writing music. It's simply impossible to keep track of it all, which means that most composers fall through the cracks.
Like the composer Harald Genzmer (1909-2007), a German follower of Paul Hindemith. Many listeners are wary of the German neoclassical school, imagining arid contrapuntal exercises full of bare fifths and fourths, but Genzmer's work stands out for its warmth and lyricism. His catalogue includes a wide array of music in all genres except opera - including a prolific output for organ that I am just beginning to explore. The closest thing he has to a hit seems to be his Sinfonietta for string orchestra, composed in 1955, which can stand up to any of the more frequently performed works by Vaughan Williams, Tippett and company.
Unfortunately, Genzmer's music is poorly represented online at the moment, and I urge you not to listen to any of the performances of his orchestral music on YouTube; the performers mean well but are painfully out of tune. Instead, try this trio for flute, viola and harp, which is not particularly characteristic of his style but at least pleasant:
Part II:Part III:Part IV:Samples from his other works are available on the Harald Genzmer Foundation page. It is well worth looking for the complete 10-CD boxset of his music on Thorofon - it seems not to have sold well, as copies occasionally surface at online retailers for fire-sale prices. If the bustling neoclassicism of Hindemith and middle-period Stravinsky is your thing, then you have hours of discovery ahead of you in Genzmer's music. If it's not, well, that's tough.