percepts

I think that when people say "perception is everything" they're wrong on two counts: (1) they use "perception" as though it were synonymous with "perspective"; and (2) "perspective" is not everything. So lets get this straight: "perception" only happens if you "perceive" some thing; i.e., you can't "perceive" something that is not real. If you see something one way on Monday, and then another way on Tuesday, it's not your perception that has changed, it's your "perspective" that has changed. But your "perception" remains the same, unless the object itself has changed in some way between Monday and Tuesday. Perception is objective, perspective is subjective: what you see is perceptual, how you see it is perspectival.  You cannot "perceive" something unless it exists. So indeed "perception" is, in many ways, "everything," but not if one conflates it with "perspective." And "perspective" is most definitely not everything: there are far more important things involved in the act of perception than my perspective of the perceived.

[If I were going to use phenomenological language, I should use the term "profile" instead of "perspective." Likewise, by this vocabulary, I'd speak of this as a conflation between the perception of object-X, and my profile -- i.e., my temporal subjective intending -- of object-X.]