This is only if you discount his early works such as The Magellanic Cloud, where he is a world communism adept wearing rose-coloured glasses, through which many of his readers, including ones in core Soviet Union, would perceive reality and future prospects.

Eastern European writers did contribute a sizeable bookshelf of writings about bright space communist future, until it began to turn sour. One lesser-known one who I remember from my childhood is Pavel Vezhinov's Death of Ajax.

UPD: Maybe we should use Eastern Bloc Science Fiction as a term?