I'm not sure about this, but there may have been two competing visions at work when Vienna's epochal Ringstraße was developed in the second half of the 19th century.
The first one is well known: a polygonal tree-lined wide avenue with monumental public buildings--parliament, city hall, university, theaters and museums--strung along as if in a necklace. This is the non-hierarchical, democratic (if you're so inclined to make such direct connections between politics and urban form) view of the Ringstraße that came to be.
But there could have been another vision, definitely hierarchical if not downright imperial. Think of it as a conspiracy urban theory if you have to. Try this: look at a map of central Vienna and mentally add a building mirroring the Neue Burg (the one with the concave façade) across Heldenplatz (so you don't think I'm making it up, this would complete Semper's 1869 Kaiserforum project.) A gargantuan figure suddenly appears, with an enormous (more than half a kilometer long!) rectangular open space extending from the Hofburg Palace all the way to the old Imperial Stables. The museums become subservient of this new composition. Even the Burgtheater and the Staatsoper would leave their place at the necklace to mark the ends of a cross axis in this figure, a giant with outstretched arms lying across the Ring.
Do you think that the Ringstraße would have survived such a broad, dominant, transversal gesture?
(And in any case, it's not so difficult to imagine how much fun Albert Speer would have had rebuilding the Hofburg's west front facing such a grand open space.)