I don’t know many synth scores but the ones that somehow stood out to me while watching the movie are Chariots Of Fire, Blade Runner, Furyo (not full-on synth though) and Never Cry Wolf.
And even when you understandably are tired of Chariots Of Fire, watching the ‘men running on the beach’ scene together with Vangelis’ famous theme, you still have to admit it’s sheer cinematic genius.