I suggest a lot of soviet composers (which there is a lot on my channel).
Vyacheslav Ovchinnikov - Symphony No.1 (where the hell is his piano concerto?)
Revol Bunin - Symphony No.5 and his instrumental concertos (viola, violin, organ, and piano concerto)
Lucija Garuta - Piano works (some kind of a women rachmaninov)
Janis Medins - Dainas and piano concerto (dainas are some really sweet music)
Otar Taktakishvili - Piano Concerto no.1 and 2, Violin Concerto no.2
Evgeny Golubev - Piano Concerto no.3 and some string quartets (we have mentioned quite a lot from him)
Levko Revutsky - Piano Concerto no.2 and several piano works (romantic ukranian)
Alexander Arutiunian - Trumpet Concerto, Piano Concertino, Violin Concerto
Erik Arutiunian - Poem for violin and orchestra (wonderful orchestration !)
Pantcho Vladigerov - Piano Concertos (5), 2 violin Concertos and piano works written op.16 onwards.
Vesselin Stoyanov - Piano Concerto No.1 and 2 (very nostalgic)
Alexander Mosolov - Piano Concerto and several piano works from the early period, Symphony in e flat major (scriabinist avant garde, except for the symphony)
Nikolai Roslavets - Everything he wrote in avantgardism?
Oleg Eiges - Piano Sonata No.4 and Symphony No.15
Orest Yevlakhov - symphony no.3 (not so convincing, but deserves a first listening !)
Arno Babadjanian - Herosagan Ballade, Violin Concerto and cello Concerto (the vc is very khachaturian and the cc has a more personal style)
Vladislav Agafonnikov - Symphony in name of shebalin (the title says it all)
Shebalin - Symphony No.5
Nikolai Peiko - String Quartets
Leonid Afanasyev - Violin Concerto
Tikhon Khrennikov - Piano Concerto no.1 and 2, 3 Symphonies and Cello Concerto no.2
Nikolai Rakov - Piano Concertos 1 and 2, 2 violin Concerto no.2
Rodion Shchedrin - Piano Concertos No.1,2,3 (no.1 is an early work)
Alexi Machavariani - Piano Concerto, Violin Concerto and Symphonies No.1,2,5
Boris Tchaikovsky - Piano Concerto, Cello Sonata and the Violin Concerto
Alexander Tchaikovsky - Violin Concerto
Aqsin Ali-Zade - Rustic Suite and Symphony No.2
Alexander Flyarkovsky - Symphony to "coeval" (kind of reminds shostakovich 12th)
Nektarios Chargeishvili - Symphony
Samuel Feinberg - 3 Piano Concertos, Violin Sonata and all the piano sonatas
Anatoly Alexandrov - Piano Concerto, Piano Sonata No.3
Gaziza Zhubanova - Symphony No.1
Vladimir Tsytovich - Viola Concerto
Lydia Auster - Piano Concerto (second movement very similar to rachmaninovs 2nd pc 2nd movement)
Andrei Eshpai - 2 Violin Sonatas, Piano Concerto No.2, 4 Violin Concertos
Hermann Galynin - Piano Concerto No.1
Eduard Khagagortian - Symphony No.3
Victor Kosenko - 3 Piano Sonatas
Sergei Vasilenko - Symphony No.3 and Piano Concerto
Heorhy Maiboroda - Symphony No.3
Janis Ivanovs - Piano Concerto, Violin Concerto and Symphony No.15,16
Gotfried Gasanov - Piano Concerto No.1
Some to mention..
Tony