Those who are critical of Asimov's Foundation series should remember that when it was written the field was rather young. Also that Asimov was rather young. Those who find it perhaps cliche-ridden should recognize it as the source of some of the cliches.
When science fiction writers have been asked about their favorite series work many, if not most cite "Foundation". The series needs no defense from me but since it's a work from the forties that remains in print to this day, well, that ought to speak for itself.
(Dismounts from soapbox.)
Those interested in more contemporary SF that gets both the technology and the people right are advised to pick up some Robert J. Sawyer.