The same four songs repeated over and over
Sorry, that's just factually inaccurate. There are repeated motifs in any score to any movie in existence, not just musicals, but to say that it's the same songs repeated is just not true.
no sense of grandeur or any reason for this to be a big-budget film beyond the opening scene with the boat
Big budget doesn't have to mean grandeur. That would be completely at odds with the plot, so therefore pointless.