I'm sure I'm gonna get blowback on this, but: The main difference I've noticed between 3.5 and PF is not mechanical, but a fundamental design philosophy:
3.5e feels like 3.5e. All its myriad of options and monsters and components work more or less together to feel more or less like its own beast. When it takes from other fictions, it is inspired by them, not making slavish copies.
PF feels like a mashup of everything you've ever liked or not liked in fiction, taken mostly literally from the source material. Gunslingers, everything from the Cthulhu mythos, half the archetypes out there are based on some specific archetype from fiction, and so on, they all combine to feel more kitchen-sinky than 3.5e. Like they're throwing everything they think players might think is cool at the wall and seeing what sticks.
Name any random monster, class, PrC, or whatever from the wide world of 3.5e content, most likely either you'll be able to trace it back to 2e, or you won't be able to trace it back to anything. Name any random monster, class, archetype, or whatever from the wide world of PF content, most likely you'll be able to trace it back to a specific published work of fiction.
I think this is only true at an intermediate level of skill. At very low skill, one isn't aware of all the uniqueifying options. At very high skill, one is aware of the single most powerful option (and there usually is one option that's head and shoulders above the rest). Only those at a medium skill level, or those of high skill who deliberately choose not to go with the most powerful option, will actually make unique characters.
But yes, among people who are of the proper skill level and mindset, 3.5e allows more uniqueness than virtually any other edition.