Late Registration is the first time Ye actually did something unique to change his sound (hook up with Jon Brion). Prior to that, I don't think a hip hop producer ever hooked up with a known movie score producer, especially right after one of his best scores (Eternal Sunshine of the Spotless Mind), to make a full length album. Late Reg legitimately broke new ground in pop rap.
But I prefer Graduation overall. More bounce. Call me a Ye hater if you must. All his albums are

to me but Graduation is the least

And that was when people started taking Ye seriously in the 'streets'.